On your last paragraph I would even go as far as saying that an actor who can make a relateable character that people empathise with which happens to be some kind of badass super-hero or super-villan, has trully proven his or her acting chops.

A good example would be “Joaquin Phoenix’s” performance in Joker (not saying the movie was good or bad, just that the performance was good, though personally I liked the movie).

A lot, maybe most, of the super-heros and villains as portrayed in movies are charicatural, paper-thin, stereotypical “goodies” or “badies”, not actually full-depth personas. Mind you, this is a thing in Action movies in general, though IMHO super-hero movies seem to go for sterotypical main characters more often than Action movies in general.