I worked remote with a SteamMachine for 3 months this year.

I did that the majority of the time, only playing games really infrequently during the week.

The only thing that can get tricky with SteamOS is security if you were to lose physical control of it. For example, you can't really use built in KDE vault yet.

They are working on that though. It is linux so you have some options if you want to manually work with it. Also, it is immutable, but if you need applications not in Flatpak, that too is easy enough. Just add Kontainer and then put a disto in it. You can then launch applications from the container directly from your desktop. No extra steps. The container remains during SteamOS updates.

I used to do the same thing with my Steamdeck, but the Steam Machine travels in a carry on and is a completely silent desktop computer. Perfect for a work machine.