The western comparison is one that pops up a lot, and I've made it myself, but the conditions are nowhere near the same, honestly. Not that it can't happen - but a lot of people who make it don't entirely understand how and why the western died and thus it often gets reduced to "there were too many of them and people got tired of them". Which doesn't quite capture the scope of it.

For a start, while we've had super hero movies as arguably the dominant film mainstay for like twenty years now; westerns were dominant for eighty. But not just that, but there were a lot of them. People complain about getting a handful of super hero movies from like, two different megacorps every year - imagine if every movie studio was still releasing their own super hero movie like they very briefly started to back when marvel first really took off. Imagine the world where that never stopped, where we not only had a million adaptations, but companies just started greenlighting every jackass who walked into the office going "I HAVE AN IDEA SIR IT'S CALLED STRONG MAN, AND IT'S ABOUT A MAN WHO'S REALLY STRONG" or some shit. Because that's basically how it was with westerns, especially after the first thirty year period of dominance and other genres (like musicals) started to take the stage; they just began to mass make as much shit as they could to save any vestige of that waning popularity they could. There was so much shit, the sheer volume of westerns outpaced every other genre combined.

But, funny enough, there's a simple reason why that won't happen with super hero movies - and it's the exact reason why so many people hate them. The big box office marvel and DC shit? Those cost a lot of money to make. Money and time. It's hard for any jackass to make one of their own, and a bad one hurts the company's bottom line and they don't like that. A western, on the other hand? Access to a rocky location, some sunny weather, and a prop department willing to look through second hand stores until you find enough battered, dusty, jeans, vests, and hats to fit the cast and you've got about 80% of the movie right there for cheap. They were relatively cheap, fast, and easy to produce for most studios, basically, and given that; they had a pretty safe return on profit which meant more would be made more often. You simply can't do that with the marvel mega films.