There have been recent leaks that indicate Valve is working on something going by the codename "Fremont" that is basically just that. Also some 3D models of a new Steam controller that's much more like A SteamDeck without the screen were included in a recent update.

We'll see though, Valve does have a bit of a problem staying focused on what they were working on when they come back from their holiday break, and sometimes things get cancelled because they lose interest over the break.