They will offer it as an optional service and charge you for it. So yes they use it.

I have tried on several occasions to like GrapheneOS. But every time I install it on my Pixel 7, basic functionality breaks. Things like receiving regular phone calls, as in people calling my number using a normal phone. GrapheneOS will sometimes not even ring and immediately display a notification saying “Missed call”. If my phone cannot be used as a … phone, what good is is?