Steam Deck is a Linux desktop device. It is literally a thin laptop with a build-in screen and joystick running linux. Does my linux system stop being that when I turn on big picture mode in steam? You can run the steam deck as your daily driver hooked up to a keyboard and a monitor.

The Steam Deck is not a Desktop ... That is like saying that every Android smartphone is a desktop. Sure, you can use it as a desktop but 99.99% of the people are using it as a handheld console.

And nice downvotes... Typical in Linux Desktop topics.