I think it's doing "OK". I wouldn't describe it as good or bad. As I've said before, I think they are setting the stage for Phase 4 and, "if" I'm right, I'm good with a couple of new groups of characters. We'll get the FF and some cool new villains, but I would rather they not rush it. I liked Shang-Chi and liked The Eternals (esp after 2nd viewing). We've got DS, Thor and others coming up so I'm not really that worried about it. Marvel took their C list characters, did the intro, built up the first Avengers, introduced lesser known characters and built them up for the IW and EG finale.
Maybe they mess it up and maybe they don't, but nothing tells me Phase 4 will not work.
Big shock here.....I completely disagree with your WRT to what WW Box office "should" be. 500M should certainly be in reach, but the BO is way off because of COVID. It might very well have hit 500 with China, but likely would have come in a shade under that. Pre-pandemic, this goes way over that mark.