First-person platforming is hard to pull off. It takes lots of planning and fine control to make it work, so Super Mario 64 playing so badly in first-person really comes as no surprise. Still looks fun though.
To make Super Mario 64 work with the Rift, YouTuber Chadtronic used three pieces of software: Dolphin for emulating the game itself, TriDef3D to render the game in... well, 3D, and Xpadder for the controls. Watch him play the game and explain how "extremely impossible" the controls are below:
You can take a look at Chadtronic's other retro Oculus Rift demos here.