I misread the comment.
> Google Voice just used to use data to set up a PSTN call. Has something changed?
Google Voice did not originally support data only calling(VOIP) like I said read the comment above me. He is supporting what I was saying.
> Yes. About 4 years ago they integrated full VoIP calling into something they call the Hangouts Dialer. Outbound works well, although I often have to initiate a call twice due to setup connectivity weirdness on LTE. Inbound basically never works, so I leave the PSTN forwarding on for that reason.
I have been on Google Voice for a fairly long time. Google Voice used to only supports PSTN calling although it uses data to trigger the call.