That's what the surface duo was. I still have my OG, and other than being fragile because its literally 2mm thicker than a USBC port on each half, its the perfect e-reader. Sadly for video consumption its not great with the boundary, but you can use it in a propped up mode which I much prefer.
Its a great phone, but certainly not without comprises, just like any folding phone.
The COTS unit shown there is not tested and certified to the contract requirements Boeing was working to. Simple as. If the price ridiculous? Absolutely yes. But you cannot go to a home hardware store and slap one in a plane.