I think the boom of CS:GO was really the knife in the coffin — not just the natural sifting of players and potential players away from the scene — but for any hope of outside support to further legitimize the game as an e-sport. In the FPS dearth of the last few years where Quake was continuing to fade and CS was segmented by the legacies in 1.6 and the ever aging subordinate Source, TF2 had a chance as a fresh and different shooter that still rewarded and demanded the core skill-sets necessary for a competitive FPS. Many of us saw then the potential and looked to VALVE to raise up a brand new exciting e-sport. Many years later, they have. They just did it with a different game.
In hindsight it really isn't a shock. CS is VALVE's competitive shooter. TF2 was always it's workshop and sandbox. They designed it one way, we played it another. They had certain notions about what it was good for. We saw the competitive potential, and manufactured rules around the game to make it function that way. The competitive 6v6 format, was always a knockoff of comp CS. Six players over five to take advantage of more classes. Gravelpit with it's attack/defend and "sites" was the comp map of choice. As the game grew, the competitive meta evolved, and we saw real talents carve out a unique competitive experience for an FPS. In that way TF2 was always sort of caught between being something very fresh and charming, and a forced version of a more raw competitive shooter.
Highlander thought it had the answer, but the game bogs down at the 9v9 level, and much of the meta-game which makes 6v6 so entertaining at it's best is lost, or — by necessity — simplified with addition of more classes. Really this isn't a surprise either, and it seems to me VALVE's understanding of the game. "Of course it bogs down." They might say. It's a pub game. VALVE's actions seem to have always supported this stance.
I believe VALVE being a generally stand-up company, they tolerated the 6v6 scene, they even threw us some bones, like that huge competitive update we had that put customizable cross-hairs and the like in the game, or the first private beta attempt where the 6v6 comp scene was supposed to help balance the game. It seems clear however, they were always honest about how they truly felt about the game. But I am disappointed to learn that they haven't even responded to that email.
Now all of this has the potential to shift with a competitive matchmaking system, which might rejuvenate the comp scene with interest from the pub scene . . . but that is a lot of ifs. Not beyond the realm of reason, but unlikely.
Do I think the game is dead as a comp shooter? No. But I do think its best days are behind it.
Prove us wrong, Valve. (buff the classic)
See you all in CS:GO/Overwatch