He returned to Microsoft (where he had been a research intern before) to work on a project that eventually became the Kinect for Xbox 360. Right after we joined Google, and currently leads AR Devices & Experiences [1].
Not sure if it's related to Johnny's work at Google, but there's some cool experiences being built on top of AR Core and Geospatial Creator, with stark resemblance to the ideas and visuals of those early wiimote demos [2][3].
(disclaimer: Googler, but on a different team; no relationship to the things mentioned here other than being a fan of Johnny's wiimote hacks :)
15 years later, I'm still surprised these proof-of-concepts didn't evolve into something more commercial.
[1] http://johnnylee.net/projects/wii/
[2] https://www.youtube.com/watch?v=Jd3-eiid-Uw
[3] https://www.youtube.com/watch?v=5s5EvhHy7eQ