Megalopolis might have been a Megaflopolis, but Francis Ford Coppola is still a respected name in film by many. His opinion is held in great esteem, which means if he declares something as not being cinema, people will take heed.
Just as Martin Scorsese was asked one fateful day, an interviewer for CinePop asked Coppola if he believed Marvel movies to be cinema. This is what he had to say:
"You know, that's a complicated question. I think there's a lot of talent in Marvel films, it's admirable. But the purpose of art is to illuminate contemporary life, not to generate money for people."
So, there you have it. While he dodges the cinema label, it is pretty clear that Coppola doesn't think the Marvel movies fully qualify as art. But, that's just one man's opinion. There are plenty of people who still enjoy the Marvel films and consider them art.
Where do you fall on the Marvel as cinema debate?