Regularly being a VR/PC player, I have never needed to use PPT, but on IOS, PPT is the only voice option, and it would be super cool if the "On" option could be added too. For the convenience of other players, a "caps lock" sort of thing could be added to the PPT button to hold it on, but to be easily turned off as well.
I run an 12.5 inch IPad Pro (although I don't think this is need to know. :D)
Your pal -