So I haven't watched most of the recent Marvel films, not out of disliking them but because I just haven't had the time to get around to them - lots of media that interests me has released in recent years and the Marvel stuff just keeps getting pushed up the back catalog - but I never really found these to be that much of a problem? I think the reason these types of jokes are done isn't because the people involved hate the source material, but just because the people on board found them funny, it shouldn't be this difficult. I'm personally more fond of when these jokes have a payoff (see: Taserface going from a lame joke to suddenly becoming a plot point in Guardians Vol. 2) but these short quippy ones are fine too, you only really notice them when they're compiled in a video like this.
I also think they're done because, well, they give people who might not be as into the source material something to laugh at. The MCU has made comic history more mainstream than it was in years prior but there are still plenty of outsiders who might not get the appeal, so doing the occasional self-aware quip can get those types of audiences on board. No problem with that as long as they're not done during a climactic scene or get in the way of pacing, which has been done and can get in the way of the scene, I agree completely with that.
As for "not being able to criticize children's movies", my position is that, well, I can't; but not because they're inherently a lesser form of media or something like that, they're just as valid as others. Instead, it's tough for me to come to a conclusion because kids - just like us - enjoy different types of media. What one kid might dislike might be what another kid enjoys - some might like sincere and honest media, others might like media that doesn't take itself remotely seriously, and that's fine. On the scale of film criticism, this self-aware attitude is nowhere *near* as important to discuss and criticize as genuinely offensive material, though this is just my opinion.
