Were you walking while filming? He wouldn't be able to showcase the differences in image stabilization for each phone if he tried to stay as still as possible.
Yes, in my day-to-day use of each camera I've been moving. I guess my point is - there seems to be a massive quality degradation in what I've seen from personal use.
Actually it is possible to show the benefits of OIS without video. It allows you to use longer shutter speeds when taking pictures in low light. Take a look at this one: