[krapp]

You're basically describing the structure of the most popular manga and anime genre in the world, and some of the top sellers in that genre have been able to keep the power scaling up for years if not decades. It isn't a problem if you do it right.

Also few superhero movies that I'm aware of actually follow that format. Even the long runners like Superman and Batman tend to only focus on one or a few familiar villains and essentially rehashing their hero's origin story every time, and in the MCU Thanos was always in the background, but the heroes themselves consisted of wizards and demigods. And Hawkeye was also there.

Batman beating Superman in any universe is just stupid, I'll grant you that much. I don't care how much prep time you have, you're not defeating a being that can bench press the moon and slice cities in half with eye lasers like Ramiel in NGE. And you're literally just a rich asshole dressed like a bat.