I hope the hiring managers I would actually want to work for would see it as a red flag on resumes

At this point, I'd assume those hiring managers are also being forced to use AI in their jobs (or pretend, at least) and probably wouldn't read too much into it if it's not a substantial portion of their resume. I do feel the same way, though.

Why? It's just the name of the game, everyone gets it. Especially if you're a generalist/frontend type.