Many of the actions taken during the Stalin era were brutal and often unjustified. Yet in the end they helped the USSR win WW2. By the 1950s life really had "become better, more cheerfull". Life expectancy had allmost doubled, living stadarts had increased massively, allmost everyone could read, even the poorest peasant had access to higher education if he was good enough, women had the same rights as men, ethnic minorities had the same rights as russians (I'm talking about systematic and state-sanctioned everyday racism. The deportations were something different, but they weren't conducted for ethnic or racist, but for pollitical reasons) and the USSR was the second most powerfull nation on earth (economicly, polliticly and militarily).
The Stalin era USSR had two sides:
The one of improving living standarts, becoming an industrial superpower, of equal rights to women and minorities, of alphabetization and opportunities for even the poorest peasants.
And then there was the one of purges and deportations, of paranoia even towards their own comrades.
Reducing it to either one of those sides would be incorrect. Both have to be taken into account.
Now to the actual scenario: A white victory would not have been better. As others have mentioned before, chances of a burgeois-democratic Russia after the civil war are remote to non-existent. Not only did many in the white movement itself reject democracy (not only the tsar loyalists), but a burgeois-democracy would've been hardly able to cope with the post-war devastation. Most of the elite would very likely prefer a fascist or at least very reactionary dictatorship for that reason.
You can be sure that in the 1920s there wouldn't be an 8 hour working day, a brief legalization of homosexuality, an indigenization pollicy towards minorities and a period of indirect soviet democracy from 1917 to 1936.
There were many supporters of the bolsheviks (actually the Bolsheviks had won the absolute majority of seats in the All Russian Congress of Soviets in 1917/18), and it's doubtfull that the whites would try to integrate their enemies into the new society the way the bolsheviks did (many white soldiers were given amnesty and the post-civil war purges were actually very limited compared to how they could have been). It's likely that millions of suspectes Bolsheviks and bolshevik sypathizers would be murdered or worked to death in Siberian labour camps.
And thats only where things start to go downhill. It's unlikely that the new government would be able to pacify the countryside, given that they would heavily lack popular support at least in the early years (in OTL, like it or not, most people supported the bolsheviks. And even many of those that didn't would have opposed a reactionary, potentially military, dictatorship). Bolshevik and ethnic minority insugencies would remain a problem for the Petrograd government for years if not decades. More bloody purges would follow to suppress these insurgencies, but their effect would likely be limited. Russia is huge and if the people don't support you it's hard to project power beyond the urban regions.
There would be no state led industrialization and collectivization (at least not on the OTL scale). Best case is that Tsarist growth rates of around 2 to 3 percent more or less continue, though not even that is given, considering the massive devastation of the war (had the whites gotten the upper hand, the civil war would at least have gone way into 1925). It's not even clear how or wheater at all the new regime would have attacked the remainders of the feudal lords. It's very possible that feudal or at least semi-feudal relations in the countryside continue way into the 40s and 50s (like in India or Nationalist China).
Now to the treatment of ethnicities: The white movement massively propagated great russian chauvinism and it is allmost inevitably that russias ruling class continues the pollicy of russification. It will very likely double down on these efforts, way more than the Tsarist regime ever did. Vocal minorities would be sent into Siberia to die or be worked to death.
Massive deportations would take place in the other non-russian territories aswell (the scale depends on which territories the whites are able to get control over. Deportations in a white Russia with Ukraine for example would be very different from deportations in a white Russia without Ukraine). Russian would be the official languages, it's very likely that other languages get baned. These pollicies might show good results in some areas, and might bread massive resentment in others. More insurgencies are basicly guaranteed. On the jews, there would be massive anti-semitism. During the civil war of OTL, Denikins forces murdered an estimated 150.000 unarmed jews in Ukraine and Southern Russia alone. A proclamation by one of Denikin's generals incited people to "arm themselves" in order to extirpate "the evil force which lives in the hearts of Jew-Communists. Anti-semitism in white Russia would not be late Stalin era "some jews cooperate with our enemy Israel so all of them are under suspicion". It would be "The jews betrayed Jesus - now we kill them!". Russias jewish population would be either directly murdered or worked to death in Siberia. It's doubtfull wheater even a fraction of the jewish minority would survive these purges at all.
Science and education would be very limited compared to OTL. Mass alphabetization would not take place. People only have to be able to read if thats neccessary for the production process. In the cities, purely russian schools would likely be established. But the peasants don't need to read, if they can they only get bad ideas. The russian orthodox church would have a lot of influence in society, non-orthodox faiths would be brutally suppressed.
Without mechanization of agriculture, Russia remains a country of constant famine every 5 years or so. It would remain the prisonhouse of nations and one of the poorest countries in Europe if not the world.
Ok so, now to foreign pollicy:
White Russias fascist/reactionary regime would try to regain the "lost territories" (i.e. everything that belonged to Tsarist Russia in 1914, maybe even more) very aggressivly. Expect wars in Finland, Ukraine (if it's independent), the Baltics and whats left of Central Asia.
The rise of fascism in Germany had little to do with the USSR. Granted, a socialist state to the east was important to the nazis OTL propaganda, but fascism in Germany rose because the elite wanted to regain what was lost in the Great War, and even more. Additionally they wanted to get rid of the archievements of the november revolution (like basic workers rights).
In OTL, the NSdAP only got 2,8% of the votes in the 1928 Reichstag election. Yet, in the following years, they received massive amounts of money from various corporations
and individual capitalists to fund their campaign. This way they managed to gain 18,3% of the votes in the 1930 Reichstag election, only two years later. Another three years later they were the only party in the Reichstag.
One of the first fascist regime did, was abolishing all workers rights and crushing the workers movement.
The Nazis re-implemented sunday labour, re-legalized child labour, abolished the minimum wage, baned all unions and murdered it's activists. Wages in Germany were actually lower in the mid 30s than they had been in 1932 (at the hight of the great depression). That is the part of the Third Reich that is seldomly talked about. Life was miserable for germans during this time, and thats before the war had started. Life only continued to become more miserable as the war progressed.
On the other hand profits for german mega-corporations only increased. Again, any workers rights were abolished, strikes were baned and KZ prisoners were rented to them as virtual slaves (the prices were as follows: 3 Reichsmark a day for a women - 4 Reichsmark a day for a man - 6 Reichsmark a day for a skilled worker). Corporations like Krupp, BMW, Siemens and IG-Farben (which is called Bayer today) profited massively from the war, too.
The rise of fascim in Germany wasn't a reaction to the USSR. Thats cold war propaganda, claiming that "in fact the commies are responsible for everything that happened, and without them Europe would have been in a state of eternal peace". Germany became fascist for mostly domestic reasons and because the elite wanted a round two.
How this TLs WW2 would develope is uncertain, and everything I could say now would be pure speculation. What is certain however, is that white Russia could never survive an OTL-like german attack. Without the industrialization of OTL, they would neither be able to build their tanks nor to power them. There would be waaay less of anything, guns, planes, trucks, mines, amuntion, etc.
Another aspect is how the Bolsheviks and USSR affected the western leftist and workers movement. Many were impressed by the successes of socialism, especially during the great depression when the USSR was basicly the only country not affected. Without that (or with only the memories of 1917 to 1925) the western socialist and workers movement would be weakened. Thats also true for trade unions.
To sum it all up, Russia would be a very poor, warmongering, famine-stricken, racist and murderous reactionary dictatorship. It would be a secondary power at best and nowhere near OTL in terms of development. Even if the white regime eventually falls to a homegrown revolution, say in the 50s or 60s, Russia would not be a world power today. Not even close. A white Russia would not have two sides - it would just be absolutely horrible.
This might sound very pesimistic but thats the way the white army was and planed to be in OTL, and thats what would happen in this TL.
Maybe this scenario would even end with a German Reich from the Elsace to the Urals, but again, thats speculation.