BNPL is a debt trap. It's targeted towards low income people with poor liquidity who are in a desperate situation for funds. It's very surprising that Apple is providing this given they target the upmarket demographic. It's even more surprising they would want to associate their brand with something like BNPL especially given the questionable ethics in usual implementations.

What if you don’t have the funds when you need to pay back later? What’s stopping me using a prepaid card with zero balance when they try to charge me? Also this will just get people into spiralling debt.