I used the Sunshine game streaming software and the WiiU homebrew port of Moonlight to get game streaming working on a WiiU gamepad. It’s sort of like a bootleg Steam Deck, and it works surprisingly well, but it mostly just made me want a Steam Deck.
At the time, Microsoft and Sony were playing this “more graphics = more better” game and Nintendo decided it couldn’t compete on that front. You can see a bit of the “compete on anything but graphics” mentality in the Wii and Wii U, then they took what worked and refined it into the Switch and Switch 2.