It's damn fun is what it is. Damn, damn fun. I still play TF2 quite regularly and love it.
KT
They wanted to make it accessible and succeeded, even going so far as to incorporate a "crits" system, but in the process the fanbase became more and more casual and less-skilled. I played TF since the Quake 1 mod days, and TF:C, and TF2, so I've played them all except the fan-made Fortress Forever. Case in point: Dead Ringer is so easily abused against typical players. Sometimes I switch to Pyro just to counter them properly because my team's noobie pyros suck too much to understand that the only way you can reliably kill the super-easily-abused DR is to light them up and blow them against a wall to immobilize them until the invulnerability expires. Stuff like that never happened in prior TF's because there was no super-easy-to-abuse DR bullcrap in the first place, and players were more hardcore back then so the average skill level was higher imho. Ditto situations like ubers and crits which didn't used to exist.
Although there's something to be said for accessibility, if a game gets jam packed full of casual fans vying to get hats or whatever, it turns off some of the hardcore players. When I still played TF2, I played to win, e.g., as a demoman on D my team almost always won because I would play very hardcore defense on capture points and carts instead of going for kills. I still ranked in the top 10 hlstatx globally all the time anyway. But I know a lot of people play casual or for stats, and it frustrates me. I used to play on two servers that was jam-packed with like-minded, very skilled players, but I think they no longer exist... not sure.. haven't played TF2 in a long time now.