Maven is just as opinionated, jealous, and terrible, but its impact is restricted to JVM packages, mostly (hopefully) in the development stage, and so the consistency issues don't come up.

I ultimately agree that the system package managers do a poor job of wrapping language-specific package managers. But you lost me when you suggested Maven has a good user experience compared to most OS package managers. If that was a sly joke, then it was a good one.