It was a golden age for the first person immersive simulation game. Wolfenstein 3D, Doom, Quake, Thief, System Shock II, Half-Life, Deus Ex - there was a period of classics with large improvements and innovation from one game to the next, where game design space was explored just as the technology to render it became available.

First person immersive sims are generally best played on the PC. When consoles that were able to do decent graphics for a reasonable period (i.e. the pace of hardware evolution slowed) came into their own, third person control worked better with joypads, and for commercial reasons, PC games often ended up as a second-rate ports of console games, with compromised controls. You really need a mouse for first person.