Maybe QM is incomplete.

Regarding black holes and information loss, almost everyone starts with the assumption that quantum mechanics forbids information loss, and proceeds from there as if that rule is an absolute fact.

But have you ever listened to a group of leading QM physicists discuss whether QM is complete and how it should be understood in physical (as opposed to mathematical) terms. There is no group consensus. Rather, there is a lot of heat and argument.

In my personal opinion, QM is still a black box theory that awaits a credible physical theory for what is actually taking place inside of the box. Compare that with General Relativity. I think Einstein will be proven right again in the end: conventional QM is fundamentally incomplete. We can use it to predict outcomes of set-piece experiments, but we are still in the dark about what it means and whether the information conservation rule is valid in the real world.