Is the issue not one of network effects? Facetime and Skype don't require you to own a video phone to make and receive calls, you can do it on a laptop or desk

Is the issue not one of network effects? Facetime and Skype don't require you to own a video phone to make and receive calls, you can do it on a laptop or desktop either to people with video phones, or to other computer users. Most of the network marketed video calls have been phone to phone meaning the number of people you can call (which network effects tell us will have a significant impact on uptake and popularity) is far far smaller. So yes, you could pull the numbers, but it's not clear what they'd tell you about the situation we find ourselves in now.