It might have some of the really cool tech that the 3DS had, such as Spotpass/Street Pass. On the flip side, it might have a lot of the poorly-conceived and executed Wii U stuff that was sluggish and clunky - everything taking forever to load, the Miiverse, the convoluted and slow storefront (the Switch is a lot cleaner, but the speed of the site is still atrocious, even with current timeline Switch’s more advanced tech).
Mario Kart (7 and 8?) would have been substantially more popular.
But, I don’t think it would have had the same trajectory as the Switch because we probably wouldn’t be getting Breath of the Wild until the following generation. An important part of the success of the Switch is Breath of the Wild. Killer applications have most often been the make or break for Nintendo - and by killer app, I mean top tier system-sellers of a given decade - so we’re talking beyond Link to the Past, Mario 64, and more along the lines of Wii Sports, Super Mario Bros, and the original Pokémon - games (or features, such as the PS2’s DVD playback) responsible for single-handedly selling in the range of 10M+ consoles. If the Switch in 2012 couldn’t manage that, it would mean fewer sales.
The silver-lining of the Wii U generation is that it acted as a cool-down period after an arguably over-heated Wii generation. In other words, I think people, after that 4-5 year wait, were ready for Nintendo’s return to greatness; similar to how they were with the Wii after an 7 to 10-year hiatus (Nintendo was still doing remarkably well in the first 2/3rds of the N64 era, but a lot of that was due to the handheld line catching fire with Pokémon and GBC).
I describe myself as a little dose of toxic masculinity.
