My local ISP offers VOIP. For a long time the area was serviced by AT&T, who probably started with phone lines and then progressed over time to dial up and the

My local ISP offers VOIP. For a long time the area was serviced by AT&T, who probably started with phone lines and then progressed over time to dial up and then more modern cable / broadband. They probably bundled in home phone service for many years. When the local ISP built out all their gigabit fiber infrastructure they probably felt they had to offer some kind of phone service to compete, and went with VOIP since they weren't going to build out a whole telephone network infrastructure. I'd bet most people don't use it, but they need to offer it to be viable for certain older customers that don't want to give up their home phones. I briefly set up a home phone on the provided VOIP, just for fun and nostalgia, but it was pretty annoying with sometimes getting disconnected and needing a manual power cycle to reconnect so I stopped using it.