BTW AMD kinda started this with their TressFX hairs (notably used in new Tomb Raider).
It had similar characteristics to HairWorks - extremely expensive feature for relatively small overall visual impact, better running on AMD than Nvidia GPUs, but still running pretty bad even on high-end GPUs.
Something to keep in mind: those super-duper features you see at GPU launch events, they are mostly just marketing, "halo effect" features, not practical enough to be used in games for almost everybody.
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We are speaking about miniscule fraction of all players who have GPUs powerful enough to runs all bells and whistles.
Titan X, the only GPU that can run Witcher 3 fast with HairWorks enabled [1], exists in so small numbers that it doesn't even show up in Steam Hardware survey [2].
GTX 980, the next most powerful GPU, is owned by less than 0.5% of all people who use Steam. And GTX 980 runs 1080p ultra with HairWorks just ~37-40 fps.
GTX 970, the next most powerful GPU, the most popular Maxwell GPU, huge bestseller, is owned by ~3% of Steam users. It's the only remaining GPU that can stay above 30 fps with HairWorks on.
So something like 95+ percent of all gamers are not affected by this issue at all.
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