Killer apps and genres by generation/system discussion

[BrayanA]

"XBox: Halo. Halo put the XBox on the map, along with the genre of FPS, that suddenly became mainstream in sales, and a phenomenon."

I don't get this. Which become phenomenon? XBOX or FPS genre?
If first - then XBOX never become phenomenon.
If second - FPS become phenomenon many many years ago before Halo.