Kinda wild these weren’t really a thing. A lot of these DAP/DACs were already running Android & many folks don’t like carrying a second phone-sized device (my DAP is small on purpose for this… well & my previous phone didn’t haze microSD for extra storage). Was it something to do with complaince for the cell radios?
The big question mark to me would be if they open source those drivers & what not or make any required apps downloadable & sideloadable. I would make something like this my next device if I knew I could flash LineageOS for microG on it & not, you know, lose all the audio stuff that makes it special. A lot of these Chinese brands haven’t even done the bare minimum GPL v2 compliance of releasing their kernels so we would have to see on that front. The ability to control your software is just as important as repairing your hardware.