There is a way to back up PS5 saves to USB.
https://www.playstat...p-ps5-data-USB/
Unless there is something wrong with that support article, it indicates you can backup save files to a USB drive.
This isn't the same as backing up saves like it works on PS4. This is making you back everything up and and then you'd have to wipe and restore everything from this backup. Not a solution they need to let us back them up like PS4 saves work.