I don't like "supers" games. The whole genre of superheros games turns me off. And I'm not even sure why. It can't be the power levels. I've run campaigns in D&D to 20th level. And it is not that I hate the genre in any media. I've enjoyed many superhero movies and TV series. I've enjoyed some superhero comics off and on over the years. But whenever I hear about a superhero TTRPG game session, I'm like, "ugh, no thanks." And I don't just mean committing to a superhero-themed campaign, I don't even want to sit down for a session. I'm thinking at the next Gamehole Con I should sign up for at least one superhero game session to see if I can either work past this block, or at least come away with a more informed opinion and maybe some insight on why I don't like them.
I think I'm at least partially agreement with you on this, but I can be a little more specific: I don't like RPGs where the players are designated as either the "heroes" and/or being the world's "main character" as part of character creation. For me, this extends to fantasy and sci-fi as well. The absolute worst case sword-and-sorcery setup for me is one where the DM starts session zero by saying "This is a world where magic has disappeared, and you will be questing to bring magic back to the land" and a player immediately says "My character is the last wizard in the world." Sorry, I'm out.
Those are stories that I like to watch on TV, read books about, or play in video games. But when I play RPGs I want characters - both mine and the rest of the party - to have to earn the title of "hero". The work and hardship is the part that makes the narrative interesting. I want to accept the premise of "no magic" and have to endure many trials and tribulations to bring back the magic. I want to play out the entire story. I don't want players to designate themselves as the protagonist. I don't want to be given super status that isn't earned.
One difference for me is I am totally okay with that sort of thing for a convention or a one shot. Just like I would ocassionally find it fun to play a video game with a cheat code, start a D&D campaign at level 20, or decide to fast forward to the end of a movie if I get bored. Sometimes, it's fun to cheat. But it does feel kinda like cheating to me, and I have little interest in investing in a long term campaign like that.
Of course, to return to the OP, I should acknowledge that not all "supers" games are like that. But the genre feels like that a lot (at least to me), and some games definitely are. I'm sure people can correct me and give examples of superhero style games that don't fit this description. Maybe someone can suggest a specific system worth trying at a convention.