This is the cop vs firefighter superhero discussion.

Batman is a cop. The very DNA of the character is almost entirely about fighting crime. His origin starts with a violent crime. Sure he’ll save people (the end of the last movie he saves people from a flood) but mostly he’s working on crime.

Superman works best as a firefighter. He’s rescuing people, controlling and mitigating damage, etc… His origin story is a global catastrophe. He will get into fights, but mostly in service of mitigating damage. He will stop crime, but mostly in service of safety. His main villain isn’t a guy who can fight him (generally speaking).

Most characters and stories have a bit of each.

From a screenwriting perspective, an antagonist can provide escalation and give a voice to the challenges the protagonist faces. It’s just a very good tool. A Batman movie where he’s just getting people out of a burning building (for example) might work, but it would feel off somehow.