If airlines were prepared to accept X in costs from lost luggage before, and now get paid Y, they can now accept about X+Y in lost luggage costs. Meaning more lost luggage! After the system dynamics resettle, from a certain angle this is basically stealing: customers pay the same ticket price, but are paying some percentage more in expected lost luggage.
And on top of that, this is just considering the financial cost - what is actually happening is that more travelers are being deprived of their personal belongings. These are worth more to people than insurance payouts! It's surprising, but when you zoom out this seems downright awful.