Well for one thing a database of biometric records gives you an immutable way to impersonate those people on any other platform that relies on the same biometri

Well for one thing a database of biometric records gives you an immutable way to impersonate those people on any other platform that relies on the same biometrics. But that's kind of beside the point. I wouldn't be at all confident that you or I thinking about this problem for a few minutes are going to uncover every possible abuse vector that a motivated nefarious actor will in the future. Collecting this kind of private data for no clear benefit looks sketchy as hell.