I think the way to really sum all of this up is this:
"Halo brought PC FPS culture to consoles and into every living room"
Before Halo the same level of vitriolic competitiveness existed, it was just exclusive to the PC gamers playing FPSs. These gamers who were in desperate need of having someone to let out some agression and play "Alph-male" a role many of them didn't get to dabble with during their daily lives.
And that's the thing a lot of people who grew up under this new regime don't realize -- that machismo was pervasive. Among Quake's multiplayer kill messages (found in client.qc) were statements about Player A riding Player B's rocket, Player A being [nailed|brutalized|smeared] by Player B, Player A accepting Player B's [discharge|shaft], etc.
"Halo brought PC FPS culture to consoles and into every living room"
Before Halo the same level of vitriolic competitiveness existed, it was just exclusive to the PC gamers playing FPSs. These gamers who were in desperate need of having someone to let out some agression and play "Alph-male" a role many of them didn't get to dabble with during their daily lives.