Nvidia LOVE hair because hair makes the benchmarks high compared to AMD. Don't get me wrong i've got a 1080ti but they do this specifically so that they can make AMD performance TANK for a very minor graphical improvement.
Its always been their way since Crysis 2. And AMD are no saints either.
The hair thing is a stupid gimmick at best, as long as amd have their version and Nvidia their version it'll get used in a handful of games at most. Then they refine it and make a big deal about it again a few years down the line.
If they could come together and make a hair system that works well on both cards it might get more use, but that's not gonna happen. So all it gets used for these days is a gimmick for a new card launch or they pay Devs to put it in their game and make a big deal out of it.
Can't say I've ever played a game and focused on the hair though so meh either way.