I've had negative responses to small, isolated submissions that I've heavily QA'd and semi-positive responses to longer ones. I think it has less to do with the "realpolitik" of the code itself and more to do with the maintainer's viewpoints about whether AI as a whole is a positive or negative thing.
I tend to respond quite well to AI-authored or assisted PRs to my project, but to be fair we maybe only get 3-5 PRs in a good month.
I tend to value person-to-person interaction. I've received a lot of purely automated responses, which shows low value to me as a person, and ultimately the project. I'm not disagreeing that code matters, but we're losing person-to-person discourse and the community that comes with it.
Thinking it through a little bit is probably coming from having bounties on a few issues that might be contributing to my negative experience.