I think art would just radically change in a new society. I'm not sure if superheroes as a concept would even exist. By this, I mean I've read somewhere that said kung fu and wuxia protagonists are the Chinese equivalent of superheroes, meaning wuxia protagonists aren't themselves superheroes but come from a similar human desire to tell stories about larger-than-life figures doing fantastical feats. But there are differences between wuxia protagonists and Western superheroes, the key different being wuxia protagonists usually become larger-than-life through training and some spiritual insight while Western superheroes are either born with innate abilities or acquire them through a freak accident. It's the difference between how the Force was characterized in the OT versus how the Force was characterized in the prequels. This is where the "superheroes are eugenics" take come from.

I think most popular iteration of superheroes (there would presumably at least be a niche audience who still want the pre-socialist conception of the characters just like how there are people today who enjoy reading medieval romances) would have their backstories radically change. There's also no reason why current superheroes can't become supervillians and vice versa as societal values radically change. I don't see someone like Batman being relatable as a superhero in socialist society. Like, Batman's backstory reads more like a supervillian than an actual hero. He's just some bourgie fuck who treats his childhood trauma by beating the shit out of the lumpenproletariat dressed in some cringey costume. But there's nothing stopping Batman from becoming a fascist supervillian. Maybe in socialist society, the Joker is treated as a deeply flawed but ultimately sympathetic proletarian hero while Batman is just some pampered and spoiled rich brat who gets off at beating the poors. I mean, this website already characterizes the Joker and Batman like this lmao