Mani ATH 87
500+ Head-Fier
The problems exist when using the mic with BT on android phones as well. It's not just related to Windows. If I'm listening to music over BT, I have to take everything off and make the call go through the phone in order for anyone to understand a word I am saying. A dedicated boom mic should work better than a tiny mic hole on a $100 pair of stereo headphones. It's lame that it doesn't.
The mic on my Mobius works fine with my Pixel 2 XL and my OG Pixel XL, so I'm not sure what to tell you. I've tried it with a number of calls and nobody has ever had trouble hearing me with either phone over Bluetooth. Hopefully the incoming fix will work for you, I agree that it would be frustrating for it to not be working properly. It's possible some users received a defective mic, or there's some software issue, or some problem with specific phones and the mic, who knows. Either way, hopefully your issue can be resolved in the near future.