Preface: I don't have any experience with Garuda or Nobara but I have used Bazzite.
Not to make the choice harder, but Bazzite does come with Plasma 6. You can have it boot to the SteamOS UI or to the Plasma Desktop.
Bazzite is a great choice for stability but you need to be aware it doesn't operate like a traditional Linux distribution since it's based on ostree and is immutable. Package installations are primarily done through Flatpak, AppImage or exported via Distrobox.
The AUR requires an AUR helper like paru or yay to interact with it that way. Otherwise you can clone the repo using git and make the package yourself.
Are you looking for scene support (double, triple, etc click events) or just being able to remotely control the light?
Worth noting several brands have cheaper "add-on" switches to use in 3-way scenarios. You would only need one smart switch and add-ons for the remaining switches.
I personally have a bunch of Enbrighten dimmers/switches and add-ons that work like dumb switches when disconnected from the hub. I too was concerned with the WAF (wife approval factor).
You can use two separate VPNs if you use a work profile to run the second one. I'm not sure if this would work for your use case though. Check out Shelter if you want to give it a try.
Is... Is that a garbage bag vest?