What secret do you use to encrypt the hard drive? That itself ends up being a password/key file that needs to get stored somewhere whether it is someone's brain

What secret do you use to encrypt the hard drive? That itself ends up being a password/key file that needs to get stored somewhere whether it is someone's brain or a more secure storage location. I guarantee you that whatever password average users pick will not take billions of years to brute force, more like an hour tops. I don't think it should have been required for Windows 11, but TPMs are a useful tool for mitigating brute force attacks.