GrapheneOS does allow you to turn it off. It has a permission switch for your phone sensors. I don’t know if there are other versions of android that allow the same.

Oh, I misunderstood. When you said screen only, I was thinking an all-in-one, but sounds like you were meaning something more like a tablet.

You can get a mini computer and mount it to the VESA mounting point on the rear of a compatible monitor. Not quite screen only, but pretty close and has roughly the same footprint aside from a little extra cabling.

I don’t think vegetable is a botanical term. So fruit and vegetable aren’t really mutually exclusive.