In the specific case of the Error 53 problem I don't see a problem. In the case fingerprint sensor has been replaced with a non standard version I really want to the phone not to boot because there is a fair chance its been compromised.

(That said I think Apple's handling of the issue was terrible and it should have given a much more specific error and Apple should have been much less douchebaggy about replacing the sensor with an official version)

That error was factory test error code -- it was never meant for end users. It was a bug, that's all. Any other kind of bug could exist that prevents a device from booting (like the recent Jan 1 1970 issue).