Likely the TPM chip. It is required for Windows Hello, Bitlocker, and a few other things to enhance security. Works much like a RSA token, if the code from the chip doesn't match the code on the hard drive it assumes tampering and will lock entry. The encrypted drive (Bitlocker) or the OS will require the Bitlocker recovery key to boot the OS (Decrypt the drive) and the password instead of the Face ID/ PIN/fingerprint you used to make access quicker. Most devices didn't have TPM 2.0 till recently, which is the version used by Windows 11 I believe.

If you don't encrypt said drive or attach the Microsoft accounts as they recommend anyone can grab the drive, reset the account password or just pull all your files from the drive from another OS. It's all forced security because the views/legal responsibility keeps looking at the companies to produce the products and blaming them for not securing their users instead of the users securing themselves.