The MCU has a few flaws, internal and external. There's a certain amount of saturation given that we used to have 2-3 movies a year? With Endgame, Downey's "death", no Captain America, no Black Widow (and whoever else is gone) material for the storyline plus Wakanda living forever, but not Boseman, that's slowed things down.
Roll your eyes, but societal changes have screwed with things. I have the impression that Feige's carefully crafted narrative found itself contending with MeToo and other "SJW" causes or whatever. Forcing "girl power", anti-colonial Black nationalism, and whatever else into scripts changed the tone of some movies IMO. It may have even changed a plot or two, nothing would surprise me.
The movies are also out of order or took WAAAAYYYYYY to long to make, produce, and release. The Black Widow movie was about 5 years too late, maybe more. The unknown virus of unknown origin as mentioned above trashed shooting and release timelines, which slowed the release of new movies. You have beloved characters gone with the round 2 characters coming a bit too far behind to take advantage of the momentum. Some stories are streaming only, but the movies build off of those streaming-only moments... They have given themselves a self-perpetuating cycle of mediocrity even with the unknown virus of unknown origin behind us...wait, MONKEYpox? For fucking real? Anyway...
A saturated market, popular characters gone, new characters are unknown and suddenly thrown into the fray, missed timelines, society having an ADHD "squirrel" moment...of course the MCU is looking rough right now.
Still better than DC's 32 Batmen, 21 Jokers, whateverthefuck happened to Harley Quinn, the Suicide Squads, eleventy5 trivial superhero characters dumped into a movie (Sharkman or something? LOL, wut), ensemble casts with absolutely no backstory, the Flash in jail, Heard in court, and Wonder Woman 1984's "whattheshit" plotholes.
But if you can get ScarJo and Gal into a kiddie pool full of Jello, holla' at ya' boy. That's the superhero crossover we deserve. Throw in special guest referee Scarlet Witch and I'll forget about the Loki series.