“ it’s usually better to just use the two different things you need”
Well, hoi polloi aren’t we spatially privileged 
But for a good chunk of the new work-from-home folks who live in small spaces, this could a nice solution. I was scoping out some wall space near our front door to put a fold down work surface, since the kids own pretty much every other spot in our flat. The trick is where does the chair live when it’s up, and what does the underside look like when it’s up.