I honestly think it's going to be in a real world situation basically 2-2.5x the Wii U. Quite short of the XBox One, but if a developer is really willing to do work and code to the metal, they can get some results that will look surprisingly close in *some* cases at a lower resolution (like how Resident Evil Revelations on the 3DS some times looks kinda like a 360 game).
That Mario Switch game looked a bit better than 3D World, but it didn't look anything close to what a Mario game on a XB1/PS4 level hardware should look like.







