First, I'm speaking from experience. The sort of players that come to the table with the idea that they are going to be that cool powerful character that they saw in the movies and who aren't happy unless that is what the gameplay validates are the ones I'm talking about.
So you are all-in when it comes to making this about players being bad people for having expectations of genre emulation from an RPG?
Surely, if someone were to sit down to an FRPG, be given the choice of playing a magician, read in the magician class that it's inspired by characters from legend and literature like Merlin and Gandalf, and then discover that all it can do is card tricks and, after a few levels, make fireworks, he might be disappointed. But, by the standard you're proposing, he would be wrong to want to play such a powerful character as he saw in the movies.
I think you're putting the blame in the wrong place. An RPG that purports to be of a given genre, and fails to deliver is just a bad RPG. Players aren't bad for expecting genre bits, and aren't unjustified in being disappointed at their absence.
And secondly, not everything that exists in other narrative media is well suited to a social RPG. Narratives tend to be filled with a lot of things that happen with the power of plot. The actual ability of the character is usually not defined in any consistent way, but is defined according to the perceived needs of the story. So typically in a lot of media you see characters whose powers and abilities vary widely from scene to scene.
You do, you often see characters that, by implication, probably have some abilities they're not displaying, or who display an ability in one scene that might've been handy in another, but, for some reason, was not used.
It makes some sense, in an RPG, to model that variability with a metagame mechanic that lets the player decide, in a game-player mode, when the PC will display some cool ability, and when he'll let it slide so the plot can progress or other characters show their stuff. D&D had de-facto done that with limited-uses quite a lot, though with a certain naiveté, being, as it was, the first TTRPG, that led to conflating meta-game & in-game.
This is one of the reasons that 'Supers' is such a difficult genre to run as a game. The internal physics of a comic book universe tend to be incoherent, and games that attempt to replicate a comic book often fail in a number of predictable ways.
IDK, I played a lotta Champions for about 20 years, and it was pretty fun, and hit a whole lot of comic-book superhero bits prettymuch on the nose.
Another very common narrative trope is 'the chosen one', where the protagonist is more special than anyone else in the story.
I an RPG, you might have a whole party full of "Chosen Ones," who, like, have attributes everyone else in the world doesn't - destinies, strange origins, divine favor, etc - and mechanics to back all that up. It'd be quite a stretch to just have /one/ such PC in a party of otherwise mundane helpers (though that's been pulled off here and there).
Sure, they could, but would it be fun?
To challenge the players with a villain doing some villainous bit from an action movie? Sure? To challenge the players with some villain doing some heroic bit from some action movie that they're enjoined from doing? Not s'much.