Are people actually playing Twisted Treeline?

Yes. People play it.

I do. Occasionally.

Yes.

I see changes for it almost every 2 patches

What patch notes are you looking at though? There hasn't been a TT change since patch 7.1 back in January. That's 6 patches ago.

Queue times for me are about the same there as in SR.

That's the only map I play for real, and the reason is that it's the only map I can function on. I don't know if I'm defected or not, but my bran does not function with going from top to bottom. I cannot play on red side, be it summoner's rift or howling abyss. I find it awkward to move around, and I cannot see my enemies. It works for me when I move forward or upward, but not downward or toward my direction.