Haven't played actively in like 3 years or so. I'll still hop in from time to time to DM/MGE/Surf/Jump because tf2 has the best mechanics of any FPS game and those 4 modes are like a concentrate for the things I love about the game.
I quit because I was losing motivation, and had actually ended up liking Overwatch quite a bit. That said, the day valve makes tf2 run well on modern hardware (source 2? TF3???) I'll likely be done with OW. Tf2 just feels particularily old these days. I also quit because i'm getting older, and I cannot keep playing at the degen hours that the game seems to operate at (especially with the timezone difference).
That said, i'm working on a personal youtube/twitch project which will probably see me making some kind of return to the game in the coming months, unlikely that it will be in the form of a competitive player though.