I’ve had updates fail on NixOS. A kernel update didn’t generate the initramfs and the system wouldn’t boot. Booting to a previous generation and reapplying the update fixed it.
This is very rare, though, and unlike Arch can be fixed without a Live USB.
But you actually own your games ☝️🤓 Well, you don’t, as clearly stated in their EULA, but their disinfo campaign was successful in selling a product worse than Steam in every way, with 0 upsides.