Its super strange, I'd run across it pretty frequently from weird super hostile nationalistic youtube comments in the past few years (flag of st George/american flag punisher kind of profile pics, nationality doesn't seem relevant), but rarely anywhere else until recently on Lemmy. I always imagined it had been common in Australia for a while but recently it seems to have broken containment.

Kind of a self own if used seriously, though. I can't imagine anyone but a little kid using rhyming slang to try to be hurtful.