I'm not part of any legion of followers of anything. The question posed by the OP was who uses FaceTime? I explained how I have used it and how, in my particular case, niche use or not, it's a success. Lately, I've been struck by the number of posts here on MR that go into this lengthy tirade about 'I never use x feature, therefore it's worthless'. That's great- if you don't need to use a feature, you're not being forced to. That doesn't delegitimize the need others may have for whatever the feature is. Video calls may not be the wave of the future or even an echo of a wave from the past. It's just a feature that some people use successfully.
OT true story, I once had a client who argued with his wife at a dinner I took them both to about the virtues of chocolate cake vs vanilla cake. She told him she preferred vanilla because it tasted better. He told her 'well, you're just wrong'. He was dead serious. We seem to be getting a lot more people who think those who use features they don't need or think important are just wrong...