BNPL is now a way of life, just like how washing machines replaced doing the laundry by hand.
Will it ever be profitable? Who knows - but airlines are never profitable too. Neither are food delivery companies. Honestly the US has bigger issues to worry about and really, probably have bigger fish to fry. BNPL was probably a low hanging fruit that was needed to generate some buzz.
It's just a matter of backing the right horse - whether that horse is Zip, Afterpay (Square), Paypal, Klarna or others.