You may scoff at this as being mere political correctness, but I say it’s about precision.

If you’re going to disagree with someone’s spelling/grammar, the precise thing to say (from a linguist’s perspective) is to note that their usage is non-standard, not that it’s necessarily incorrect. Because we all know prescriptivism is for losers. ;) (And the “wrong”/non-standard way to spell it/phrase it will probably be the “right”/standard way in a few decades.)