The entire point of Bazzite and other immutables is that you get a rock solid system that you never ever have to worry about breaking.

Atomic updates means updates either apply or don't: there's no partial/fail state that can stop your PC from working. And in the rare event that an update has issues, you can instantly boot the previous two images, without typing any commands or using any fancy restore tools. And if you're a bit tech savvy (ie you know how to type a single command), you can even go back upto the last 90 days worth of images (via github).

The best part of atomic updates is OS upgrades, they work flawlessly. In fact since updates are delivered as images, an OS upgrade is no different to any other regular update, unlike regular distros like Mint where you have to cross your fingers and hope that your system still works after a dist-upgrade (and I believe Mint's official stance was that they didn't support dist-upgrades, they recommend you to backup, format, clean-install and restore with every OS release. Not sure if that policy has changed now, but that used to be their stance for a very long time).