JJohnson scenario has racial relations being better than even modern times.
I find it...reasonable....and it's main problem is it hits our biases.
Logically we 'get' that society that frees its slaves not under duress feels reasonably confident in itself. It's also logical to assume that a society could choose to not do things like lynching, setting dogs protesters or stealing the property of free blacks. Refraining from doing so does tend to engender more good will in comparision to those societies that engage in such practices. If you start from that as a starting point after a 100 years or so you could end up with a society with less recrimination and "history" than otl.
I think this reasonably possible. I also think, selling this idea to the majority of posters on otl present day Alternate History.com who care about the American Civil War is more ASB than a successful Sea Lion.
The illusion of slavery is not being shattered by a late victory, if anything it would be vindicated and reinforced.
After you have a ton of freed blacks, armed blacks, worst of all educated blacks, going back to antebellum conditions is not possible. You could and probably would try, but it wouldn't work.
The lost cause revisionism was caused by wrong ideas, not resentment.Many falsehoods were promoted, trying to link the resentment to the policies "pushed" on the Southerners doesn't work because it ignores the amount of revisionism that was applied in the subsequent decades and the propaganda that shaped the creation of anti-black groups.
Yes, there were a lot of wrong ideas as well as some right ones, like the Yankees had more factories, and people. But, I think it defies common sense to suggest that lost causers didn't resent losing the war. To say policies and laws were laid down that White resentment to those polices didn't have something to do with the subsequent treatment of black people is to defy logic.
It is also reasonable to suggest that, without that resentment, behavior toward black people would be improved in some atls.
Having slavery being protected nationwide over state rights shows that short of revolution slavery can hardly be abolished without very strong popular support, something that I cannot see emerge short term.
1890 or 1900 or 1910 would be soon enough. A lot can change in 30-40 years. Dieing to defend slavery doesn't mean you won't mellow with age or that your children or grandchildren would do the same.
Do I find Cleburne's memorial being accepted as working, probably not. In fact Cleburne keeping his mouth shut, being promoted to Corps command, and doing something bigger during the Atlanta Campaign would be a more believable PoD. But long term, yes, I could see the Confederacy eventually becoming a reasonably decent nation and I think the legacy of the otl blinds us unreasonably to that possiblity.
The Confederates were not the noble hereos of the lost cause movement. But they are also not the cartoon villians that I sometimes feel they are portrayed as in modern media. I think we have not yet found the proper distance to see and judge them.