Why worry about black hole info?

Physicist Sabine Hossenfelder, aka B, answers:

Dear Dr. B,

Why do physicists worry so much about the black hole information paradox, since it looks like there are several, more mundane processes that are also not reversible? One obvious example is the increase of the entropy in an isolated system and another one is performing a measurement according to quantum mechanics. ...

B: ... This problem has attracted so much attention because the mathematics is so clear-cut and the implications are so deep. ...

Excuse the cynicism, but that’s my take on the situation. I’ll even admit having contributed to the paper pile because that’s how academia works. I too have to make a living somehow.

So that’s the other reason why physicists worry so much about the black hole information loss problem: Because it’s speculation unconstrained by data, it’s easy to write papers about it, and there are so many people working on it that citations aren’t hard to come by either.

She gives more of an explanation, but as you can see, there is no good answer.

Burning a book destroys information. It is an irreversible process. Some theoretical physicists have a quasi-religious belief in reversibility, so they do not accept the information loss. But instead of arguing about what happens to a burning book, they argue about what happens when you toss a book into a black hole. That way they can say whatever they want, and no one can prove them wrong.