The "superhero movies aren't REAL cinema" argument is the latest variation of the eternal "popular vs. good" debate that has been raging forever in all forms of artistic expression. It will never end because there will always be a difference between critical and popular tastes.
This particular version of the debate is extra-vicious because comic books were long dismissed as juvenile and superheroes as the most absurd form of fantasy, but now superhero movies have become the most popular form of entertainment.
That reinforces the central conviction of the critical elite that they have more refined and intelligent tastes. They LOVE this cultural moment, despite their protestations to the contrary. It "proves" they're grown-ups in a world of children.
What's more delightful for those who see themselves as elites than getting together with others of their caste and sneering at those who pay millions of dollars to watch people in costumes punch each other? They're enjoying this cultural moment as much as any Avengers fan.
It works both ways. It's fun for people who enjoy these splashy entertainments to chuckle at the smaller group that would rather spend $20 to watch a movie about people sitting around and arguing with each other. The tension between popular vs. good is maintained by both sides.
This has always been the case with movies because the cost per hour of the entertainment is so incredibly high. You get 90 minutes to 3 hours for $10 to $20 these days. Nothing else costs so much for such a brief experience. Of COURSE people love extending it by arguing about it!
A generation that came of age with more serious superhero stories and comics is making and enjoying movies now. You can time this quite precisely with the advent of the modern superhero summer tentpole blockbuster. It's a proxy for the usual sort of inter-generational argument.
The ironic thing is that superheroes are not so much different from the demigods and legendary heroes of classical myths that are seen as the foundations of serious literature. In some cases, the superheroes ARE the very same characters.
You can tell great stories with such characters and legends as building blocks. You can tell simple but highly entertaining stories. And you can tell lazy, silly yarns or stories for children. It's all in the execution. Every era rediscovers fantasy and myth in its own way. /end
