I think you missed the crux of the issue: in a lot of companies, Agile is definitely waterfall-ish, with a lot of pre-planning, design working a few sprints in advance, a lot of "getting it perfect" during PR reviews, no follow-up, no evaluating the work midway, no admitting failure and reverting it before finished, etc.
> Having roles for operations is not incompatible with DevOps at all.
I think you also missed the problem on this one. If you have "roles for operations" that doesn't involve development, it's not a devops role, it's just an operations role. Sure you can have devops in the mix, but someone doing operations exclusively isn't devops.