The first comment, which is a screenshot from Mastodon, is perfectly acceptable. There is a clear regression between newer versions of rsync.
Then egos got bruised and things leave the realm of reason soon after. But coming with a request saying "Version X worked while version Y doesn't", with maybe some degree of annoyance, is fine.
This doesn’t seem related to my comment. Did you mean to reply to me upthread?
Saying ~“maybe it’s not ok to do <thing> but <reasons they might do thing>” is nothing like your example and does imply it’s acceptable to the speaker to sometimes do that thing.
But we’re past that now because the person I was discussing this with has gone ahead and clarified that telling an open source maintainer to please stop fucking up isn’t an angry comment.