Plus it takes so freaking long for the total payoff.Interesting. I have found the opposite with most in that finally we can move this story forward because all of Phase 4 was one big What the hell are we even doing in this universe now?
You could take time to set up Thanos because it was the first time we did all of that. Now MCU fans know how they roll and you can’t take as much time to get to a big story or you lose the audience. Doing a 20-movie endeavor like they did with the Infinity storyline will never, and can’t ever, happen again. They will lose their audience because nobody has the patience for that again once it’s been done.
The first took about 12 years without the pandemic.
Edit-They also mostly hit a home run with the casting of the first series, they won't always be that fortunate.