> What's stopping IDScan from "delegating" the storage to another company so they're no longer liable for stolen data?

You can't really delegate the liability to a vendor. Of course in current world it means nothing since there is effectively no liability anyway, but if we're dreaming of a world where there is liability, you can't delegate it. You can delegate the operation, but not the liability.

The company is responsible for vetting their vendors so they meet their requirements. Today that is done with a silly dance of exchanging SOC2 reports and such, which means nothing. But if there was actual personal liability for the board and executives, that would change in a millisecond.