I think he has a tray underneath? I'm also concerned that over time, those wires are going to get nasty and you are going to get bumble foot and other foot health issues.

I've been wanting for a while to get button quail. Can put 3-4 or so in just a fairly small 40g or 55g aquarium works great or any custom made thing. Some of the bedding options on those are easily scoopable and like millet serves double duty. Granted again I realize thats for pets not for meat production. (Could give the tiny eggs to lizards at least) Just pretty much any animal I've been ever interested including birds, the bare wire wasn't ever great.