@rain On the receiving end I would be totally fine with either treatment. Happy to have it merged at all, usually.
Devil's advocate: if they hoped to continue making more ongoing contributions, that elided dialogue around helping them land it themselves may have also helped them better internalize the standards and idioms of the project. At least, for the subjective pieces that can't just be critiqued accurately by CI or gleaned from any existing contributor guidelines.
@shane Depends, usually I'm talking after 1-2 rounds of reviews
Last substantial contribution I did this with, the contributor had done all the background research (thank you!) and 90% of the work, and it would simply be a waste of everyone's time to ask them to do things like change type and method names
@rain I think there can often be value in the back-and-forth as a teaching tool, though I think good maintainers can also sometimes tell when it's not desirable.
On the flip side, it's not great when the maintainer's edits make the patch completely wrong. I did once have a maintainer take a small patch I wrote, replace it with a completely different small patch that was incorrect, and land it with my name attached. (I think that may have been my only contribution to libX11.)