When talking about a camera for video conferencing, having especial high resolutions does not matter. Having good quality 720p (sharp, little noise) is way better than having bad full HD. Even TV in 720p holds up pretty well on large screens as long as the source is good quality.
Unfortunately the cameras in Macbooks are not of the "good quality 720p" kind. They make blurry images with lots of noise, have poor low light performance, and the colors don't look right.
Facetime on iPhones is a lot better than Facetime on Macbooks
