Samsung really does not want people unlocking their devices. With the Galaxy Z Fold 3, unlocking the bootloader disables the device's cameras. While seemingly a software lock, it is not a good look for the South Korean company.
https://www.notebookcheck.net/Galaxy-Z-Fold-3-An-unlocked-bootloader-disables-all-cameras-on-Samsung-s-latest-foldable-smartphone.556652.0.html