If he was banned for that, it would be total nonsense. It's just a screenshot, not plagiarism. If it's plagiarism, probably half of forum members should be banned, because most of us have uploaded some screenshots to Bitcointalk. Plagiarims would be when someone upload things like stock photos without legaly obtaining it. How about posting memes without putting credits of creator - is it also plagiarism?
I think OP ban isn't related to that post. As guy above said, maybe it's possible that he was in Yobit sig campaign, one of his posts was reported and deleted and he got 60 days ban.