I suppose. It's just that the attempt to spin an aesthetic issue into a generational/political issue doesn't look good when the side generally doing that makes a howler like that.
The truth is that the MCU is very much a work by boomers and it runs largely on boomer nostalgia. Think about it most of the Marvel comics characters they make movies about come from the '60s, during the teenage and adolescent years of boomers and it's through boomer engagement that these characters and comics became prominent. I guarantee you that most of the young people who see the MCU movies or buy the merch haven't read the original comics, so essentially the MCU is a vehicle for boomer media to expand to a new market and new generation of consumers.
So essentially, as Alan Moore said it's the culture and adolescent nostalgia of one generation is sitting over that of later generations.
I guess so. It's probably what Scorsese saw as a means to get his voice heard above the crowd. Not that he doesn't believe it, I am sure he does.
The two issues are definitely related however. The mainstream movies is downsizing so-to-speak and what takes over is something entirely different in Scorsese's perspective. From his POV, if a bunch of movies with only a few surface stylistic quirks but overall visual conformity in terms of lighting/color grading/staging of action/stunt choreography/VFX become so successful that other producers start going in that way, then that means that the director-with-a-personal-vision and style has a smaller place than before.