There are, basically, no Nazis any longer---a few crazies here and there but, unlike communism, it is a movement that is utterly dead. Marxism has an elaborate philosophical edifice; Nazism did not---despite the writings of guys like Carl Schmidt: It was a personality cult around Adolf Hitler. This is part of the reason that there was no Nazi insurgency in Germany: With Hitler dead, it was not clear what Nazism was any longer.
But when people call you a Nazi, it is much like when they called a woman a witch in the middle ages, it is just an excuse to kill you. There were no real witches, but there were people communities wanted to be rid of. Similarly, despite Nazism being an utterly dead movement, accusations of Nazism are still politically useful.
That is how you get Jewish people like Ben Shapiro and Zelensky being called Nazis. It is an obvious absurdity---but then again, so were witch trials.
When Russia calls Ukraine "a bunch of Nazis" they are just taking advantage of the memory of the war with Germany to incite the Russian army and Russian people into genocide. I suspect the Russians will just keep making this fight uglier and uglier until it does degenerate into genocide. And yes, I don't use that word lightly, but when you have Russian soldiers raping women and saying "I do this so you won't have children of your own" some genocidal intent is obvious.
The "Ukrainians are Nazis" line really means "Let's kill the Ukrainians."
I guess nationalistic socialists can themselves "social nationalists", ha ha.