It stuck because of how they reacted to it. If they had reacted the same they've done by being called fascists, racists, nazis, misogynists, paedophiles etc. it wouldn't have become a thing. But the one thing they can't handle being called is "weird", which is in itself extremely weird. I'm all for absolutely overusing this and finding other words they can't handle, it's hilarious to see them so clearly show that they're just mentally 3-year-olds having angry outbursts.