Add a keyboard, mouse and monitor, which are already required for every other pc, and you can do everything on the steam deck that you can on any other pc. The steamdeck just has the additional functionality of working without those if you so choose.
Im sure you could find a usb c camera that could easily be obscured or pinned to a lapel or otherwise disguised for cheaper than the price of a pair of smart glasses, or even just wear your phone on a lanyard around your neck with the screen facing your chest. People might think its weird but noone is going to second guess it unless your phone is in your hands actively pointing at them.