@Patrick Well, that is why I said I'd "double down" as I didn't originally say anything about other non-Marvel movies before that post! And if it frustrated you, you know, fair enough. However, I
would say that a good chunk of the movies prior to
Endgame *did* have ambitions beyond pure spectacle - whatever you think about
Iron Man, it is absolutely playing with the War on Terror as a theme (there's an argument to be made that despite Stark's narrative path in that film, overall it's a pretty pro-War on Terror film! But that's a whole other rabbit hole).
Captain America: The Winter Soldier, I would argue, is, in part, about the military industrial complex spying on the citizens of America! And so on, for a good chunk of the other films,
Black Panther in particular like you mention. I acknowledge there was a formula there form the beginning, for sure, but at a certain point (I'd argue around
Doctor Strange, specifically, actually, although I haven't watched that movie in a long time so I may misremember deeper themes it might've played with), the movies trended more towards the formula
only with far less substance than before (I cannot make the argument for every Marvel film before it, either. Some of them were bad and very shallow. And I'm fine with dumb fun, generally, although I would make the argument we're past the sell-by date on that for these films, too).
I just cannot see anyone watching
Thunderbolts and coming away with an interesting reading of it beyond something like "it touched on depression a little" (and, hoo boy, I would argue "a little" would be doing a LOT of heavy work in that argument). You can do that with several of the earlier movies - heck, for all I know, they'll get their mojo back and you'll be able to do it with the next
Avengers (though I doubt it). But I don't think it's just Marvel or comic book fatigue that is making these movies make less and less money and being regarded as lower quality lately (even Deadpool parodies this with the line "Welcome to the MCU! You've joined at a bit of a low point" in the
Deadpool & Wolverine movie).