The shittalk, pain, hairiling and the other stuff is all great.
But what really gets me is the struggle, the struggle to beat someone. Total domination is good but a struggle is x100000 hotter, if you're watching your friend, partner or winner choice(When i watch fights i like to pick a fighter) struggle, feel pain and get damaged and see if they can overcome that pain in order to win. The struggle is the hottest part of the fight, while they are in pain to overcome their opponent and win is the best feeling ever better than seeing total domination.
I've always said, if your wife loses she doesn't love you as much as the other wife loves her husband.