Hot take, but I see it having a market for people who just want to play on a tablet dedicated to gaming without futzing with peripherals. During break I stole my daughter's tablet to play Gameboy games and it was possibly better than my deck (lighter weight, bigger screen, and shaders that give it a pixel grid w/ a GBC border frame).
This big thing is still not for me, though, as I'd prefer the versatility of going portrait mode because I would likely use it as a 3DS emulator depending on how good the touch is. DS screens fit quite comfortably on tablets in portrait mode. (Assuming I even have the disposable income, which I do not).