Really should keep that PPA use to a minimum. They're potentially a source of not just instability but possible malware as you're putting a lot of trust in whoever maintains that resource.

Break your system and it's broken.

How unexpected!

OP hasn't used AUR much

nix flake update
nixos-rebuild --switch --flake .

# Just to keep an update history
git add flake.lock
git commit -m "update"

This may seem like too much work, but it guarantees an all-or-nothing procedure. If some package is broken, the entire upgrade process is canceled, and the system remains in the state that it was.

I have had a couple of partial upgrade cases on Arch. It was not fun live booting to repair it, every time this happened.

When I use Debian/Ubuntu, I prefer installing missing/outdated software from Nix package manager or Flatpaks.

This way, I can keep a stable core, while being able to enjoy all the latest versions of the apps that I need.

I find debian more stable than arch, especially when updating.

presses the big blue 'update' button in GNOME Software in Fedora