Has any online leftist ever talked to an ancap? It's not that they suppirt oppression outright, just that they don't care if it doesn't affect them. That's why their ideology makes sense: they don't consider that they'd be the proles, they'd be the capitalists.
Coincidentally, that's why most authoritarians support their brand of oppression: in their specific genre, they're the winners and the losers can go fuck themselves. And no, they don't consider that they're just paving the way to their ineviable overthrow