DCC should be illegal - full stop. Any country with a reasonable consumer protection function should ban it outright and hold criminally responsible anyone who does it.

It is a scam. It is never *not* a scam.

No reputable firm should engage in it or allow their franchises or partners operating under their brand to engage in it. Of course, I've never considered Airbnb particularly reputable, so I'm not surprised they're peddling this scam on their users.