Could you please elaborate?
USB 2.0 data transfer rate usually tops out around 30 megabytes a second. Rather less than you need for an uncompressed video and audio stream. Internal to the Wii there is also nothing you can really do compression with in real time either.
Beyond that the Wii was already an abomination of technology when it was made (it being a juiced up gamecube for most intents and purposes) and 5+ years on... well one need only really take a look at the game desert that was the wii past about year 2. Years 6 though 10 or so would not have made things better.
The wii U then being a remote possibly second screen might have allowed a few types of games to appear (while it has thus far been a failure in terms of local console play the PC and handhelds have done what is effectively the same thing in game theory terms for decades, and been monstrously successful in it) but it would probably have still been a hard time for devs to do that much, or they would be held back by tools not being updated. You might have got a few devs really make it sing (it does seem to be a fate of consoles that it takes about 5 years for the devs to really get to grips with a new technology).
One also notes the general failure of in place upgrades in the market -- you have what maybe hard drives on the 360, the gameboy color (which we should probably remember still saw many devs playing to the original for many years after that with true GBC exclusives being rather thin on the ground), maybe if you really squint the n3ds got a few exclusives worth speaking of, possibly the N64 expansion pack (though it was cheap enough that Donkey Kong and Perfect Dark was enough to justify it for many), the PS1 analogue controllers, possibly the Amiga upgrades but that is still dubious... anything else (N64dd, super game boy, xbox one x, ps4 pro, dsi, 32x, megacd, most of the online devices for the SNES and megadrive, kinect, ps3 move... all bar the DSi might have had something interesting happen on them from a gaming history and history of mechanics/franchises perspective but all limit their market massively to the point where most devs might throw a deeply optional perk to them and consider them a bad investment to do anything unique to).
To that end.
Likely. Would have crashed and burned. Maybe a handful of devs paid to try their hand and some homebrew.
Optimistic. Would have been a home to a handful of interesting games and a lot of shovelware.
More pessimistic. Would have been a home to a bit of shovelware, particularly if it took off in some region (possibly Brazil or Korea)
Dropped some psychedelics and now in the dimension of wishes and fairies. It dropped, was bought by essentially all wii owners at that point, possibly as it was so cheap or came with a mega game collection. We then saw a mass exploration of local co-op and local multiplayer with the benefit of a hidden second screen for one or both players allowed the exploration of a game theory concept called imperfect information. Real time strategy, card games, curious platformers, party games, no screen looking in first person shooters/mario kart leads to better options there, inventory management and maps are improved massively beyond even what the wiimote allows, all flourish and as devs don't need to spend millions doing skybox textures (it is 480p after all) we see even more experimental stuff as risk is not as high.
Of course that could have happened, indeed was more likely, for the Wii U and look how that turned out. Granted the Wii U had its own faults (if the Wii was a hardware abomination then the Wii U was what happened after the drunken evening resulting in the Wii became chain smoking crack, and massively outclassed without providing many benefits, such that most of the big players in the industry abandoned them in a hurry -- see lack of then modern unreal engine) so there is also that but even so if devs had really wanted they could have got it going on; some of the PS360 ports are among the best non PC versions of those games like the Dreamcast stuff is today for the PS1 and N64 era, and overlooked about as much at the time.