La Plata is only an iconic thing because anglos don't know Latin American history, it was literally created because back in HOI2 you had a limited amount of tags so some minnor countries like Uruguay and Paraguay were recycled to other purposes. Also nobody in Uruguay would support joining Argentina, less one that is a dictatorship.
Atlantropa was not erased because "realism" it was erased because it brought problems to the Balkan and Turkey teams (because how in the hell do you determine the borders in things like islands) and because ultimately the mod didn't account for Alantropa. Like the Mediterranean countries didn't have a mechanic of "holy shit, we have lost all of our ports, we need to rebuild them, also our economy is being hurt", so if it doesn't impact the game at all, why have it?
Same thing with the US lore changes, TNO USA said that the New Deal didn't happen but it didn't want to account for how the American political system would have changed without it, so Mango decided to brought FDR back, if at the end of the day it didn't change anything.
In general I find that the "realism" complains have no merit, like people who complain about the Commune of France or Germany being reworked in KR, what devs are doing now is trying to study politics, movements and other things before deving. "Wikipedia deving" generates things like KR Uruguay which are horrible.
I think that TNO is characterized as the realistic Axis winning WW2 scenario, because it was a change from back the media was back in the day, but the three-sides cold war for me is more iconic that the German Civil War. If the Russian warlords were to be removed then I would agree with the "soul of TNO arguments", because TNO Russia is one of the elements which set TNO apart.
I am biased for saying this (Uruguayan and TNO dev), but for me now TNO is great because of its South America, is the best representation of the continent in any HOI4 mod. Its devs actively do the leg work to do research and check primary sources to see what interesting things they can add. Adhemar de Barros being elected in Brazil or Frondizi surviving in Argentina are unrealistic, but they are interesting scenarios and stories and the lore for those scenarios has been well-researched by its devs.