The difference between the phone provider and Zoom/Hangouts/etc is that all you need to join a zoom call is install an app in about a minute, or follow a browse

The difference between the phone provider and Zoom/Hangouts/etc is that all you need to join a zoom call is install an app in about a minute, or follow a browser link and you're ready to go. People want convenience. Tools are there to serve us for as little effort from our end as possible. Zoom does that. And even for audio calls, people will often prefer private gardens like WhatsApp, FaceTime, Skype or whatever to simply avoid the cost of a carrier call because you can't beat free and easy.