i7-6700k should have PTT. Whether your mobo can enable it is another matter. As someone said, that CPU isn't on the approved list. But it might be by release. They're "evaluating" 7th gen right now.
I would say the situation hasn’t changed enough for Rapid’s advice to be any different.
Also, the 3090 isn’t much more than the 3080ti, if you can find any that aren’t tied to stupid bundles.
If this hasn’t changed, it should be ok. But please let us know when you try it.
https://forum.virpil.com/index.php?/topic/2773-vpc-helicopter-collective/&do=findComment&comment=27743