The only time I get to watch those are when I'm on a transcontinental flight, they always have them 100% in their list. It's one of those weird things where they are apparently really popular although I personally know almost nobody who watches them, and I do know some consoomer types who faint over Star Wars and stuff like that.
I honestly don't get appeal. The world is ridiculously oversaturated with magic, aliens, sci-fi tech, etc. while the only concept of a good superhero movie would be one where you learn about the origin story of the hero and the villain and where they got their powers from - you know, some sort of build-up. I know Marvel has this stuff too but in those all-star movies like The Avengers it's just bloated and doesn't matter anyway because it is dogmatically stratified into "power levels" instead of a stone-scissor-rock principle where one superpower trumps the other, which would be more interesting to watch. I just think anybody who gets invested in this and is over 18 has problems. Like, this is kids stuff. At least for Chrisopher Nolan's Batman trilogy I can at least activate my suspension of disbelief during the more serious moments, for Marvel movies I can't.