The man isn't saying anything outlandish when looked at as not an attack but a comment on what he feels is the equivalent of the films.
The fact people get defensive and start trying to undermine the achievements of such an amazing director, for Marvel of all properties in cinema, is insane. You can disagree with the man and even call him out for it, but insulting his work to defend marvel is just... Wow.
Eh, his first comment was kind of lacking. He was asked if he's been watching the MCU (because that's THE big thing in movies today), and he says he tried, but they're unwatchable to him, because they're "not cinema", and they're not "the cinema of human beings trying to convey emotional, psychological experiences to another human being."
People can be forgiven for thinking that that's a specific attack against the MCU movies that they found emotionally moving (although responding to that by trying to insult Scorsese's work is wrong and stupid).
But then, Scorsese has the opportunity to make a longer, more eloquent statement, and it seems that he's upset because he had to go to Netflix to get his latest movie made, because studios don't want to invest in high art anymore, they want to maximize their profits with blockbusters, and even if you get your film made with Netflix money, cinemas won't give you screens to run your movie.
"It's not cinema, it's something else," he argued. "We shouldn't be invaded by it. We need cinemas to step up and show films that are narrative films."
Sooo... he's not even talking about high art/low art anymore (his definition of "cinema" was lowered as soon as he called theaters "cinemas"), he seems to be arguing that blockbusters [Marvel movies?]
are not film. That they're not "theater movies".
And then, he seems to suggest that George Lucas and Steven Spielberg are cool, as if Star Wars and Jaws didn't create the monster that he's railing against.
He's definitely got some things to say, but I don't think he's doing a good job of saying it, and he should probably stop using "Marvel movies" as shorthand for "blockbusters" (if that's even what he's doing, he might just be a DC/Snyder fanboy with a mad-on for the MCU).