I remember being a college freshman in 2001 and playing PC games, namely Rogue Spear and Counter-Strike online with friends in my dorm room. I talked with them on a headset with a microphone using Roger Wilco and Battlecom. A lot of the guys I lived with in the dorm thought it was really weird that I talked to people online playing video games. Some would make fun of me.
Then Halo came out in November, and in the spring semester, when everyone returned to school after the holidays, and a lot of people had new XBoxes with Halo, nobody thought it was weird anymore. Almost overnight, online video games became normalized, at least to college age dudes.