itsjpb you'll need to go into recovery mode, wipe and reinstall GOS from scratch
ADB can't uninstall system apps globally, thats's why you add --user 0 (user 0 is the owner user, you can uninstall for other users too) in the pm uninstall command.
A factory reset wipes all the persistent state, and since ADB cannot modify the system partition (Even if it was able to, Verified boot would revert all changes on next boot) an system app's uninstall is stored in the persistent state.