There’s literally nothing stopping them from fixing the bug in either this case or the hypothetical. The maintainer just doesn’t respond to email from .ru domains. He could still choose to take the patch. He may just have decided not to accept this patch because changing something quite obscure to fix a weird printer used by one guy is likely to cause more problems than it solves. We don’t know because he didn’t respond.
That certainly doesn’t mean he wouldn’t fix a serious bug just because he heard about it from a .ru address.
He's saying that they can not accept the same patch, even from someone else, once it's been submitted by a sanctioned country. It's little to do with getting a reply.
I haven't verified if what he's saying is true though.
There’s literally nothing stopping them from fixing the bug in either this case or the hypothetical. The maintainer just doesn’t respond to email from .ru domains. He could still choose to take the patch. He may just have decided not to accept this patch because changing something quite obscure to fix a weird printer used by one guy is likely to cause more problems than it solves. We don’t know because he didn’t respond.
That certainly doesn’t mean he wouldn’t fix a serious bug just because he heard about it from a .ru address.