When you haven’t applied the backups you created, you are actually in an in-between state of uncertainty. Will these backups actually work when you apply them, or not?
The simpler your backup mechanism, the less brittle they are. If you have a myriad of steps they are actually quite interesting and the chance of failure increases with every step.
You can trust in the system, but trust without verification is just hope. Open the box and make sure your cat is alive.
You can take backups with for example Restic, pair it with Nix and you can forget about it.