I'am not, those are flatpaks, that's not the same as system wide installation. You can't change system files on the deck unless you unlock it, and even if you do that your changes will get reverted next time there is an update, because that's how he system is designed to work, every update a clean slate.
I own a Steam Deck, reserved it on the first 15 minutes. I use Linux daily as my main OS for almost two decades, coincidentally most of my machines are also Arch based. I know what I'm talking about. You don't want to use SteamOS for your daily computer, the system is purposefully handicapped to work as a console, if you're doing the occasional browsing or text editing it works, the moment you need to touch system things it goes down the drain very fast.
I'm not shitting on the deck or SteamOS, I have a deck and never even considering switching the system. But you need to know the limitations of it. The system is designed for gaming, trying to use it as your main computer is bound to give you headaches even if you know your way around Linux and can think on appropriate ways to bypass the limitations, from things like podman to user services to overlay fs.