Kinda wanna know why Prototypes, Jas, and oov are gettin' the -frags because there's plenty of truth in their statements.
1. TF2 is fuckin' boring to watch unless you have a legitimate vested interest in the players who are playing. Not even going into match and LAN delays waiting for all 12 people to get ready, holding and defending are two of the most boring aspects of this entire game. Even in CS, a slow game in regards to player movement (ie. walking = no footsteps), you're not gonna have to wait four or so minutes for the next piece of action to happen because someone's around a corner with an M4.
2. While we've got 50 teams in Open alone this season, the point that we're a tiny niche in comparison to TF2 at large stands strong. People don't care about the game because Valve has turned the front page of it into trading and 24/7 chokepoint "feel good about yourself for being able to shoot down a narrow hallway with your dildo-covered hat" map servers. Most anyone who honestly cared about playing this game as a team in pub servers left a long time ago. TF2 is easily on forced life support with how sharp the degradation in community quality has been these past years.
3. People who actually care about comp play want to watch big names who are in the big leagues (or who have been) stream their games and cameradudes stream big matches. Everyone else ranges from 2 to 6 viewers at best from what I see in the sidebar.