I will chime in here with my own theory. People today, particularly the new tech generation, are totally absorbed in themselves and their own little bubble. That is why they do vertical videos, its about them and how cool they are to be "getting this." They are not thinking about the guy - the user - they are handing it off to.
It is no different than all the terrible websites you come across that cause you a lot of time to find any information. Take the website from one of the largest communications companies in the country; if you go to that website you have to search and search and search just to find the right page or right button to pay your bill. Its awful and its like most of the websites you go to, the websites were designed by a guy (or girl) who was thinking about how cool he designed it. He didn't design it for you the user! You want to find user oriented websites? Go to a porn website and they make sure its user oriented and are an example of how to build a user oriented information system.
I see the same thing more and more in engineering reports and government policy documents I work with everyday. They tell you little and have a lot or words. The reports aren't made for you - the user - they are made to be really cool.
So, the vertical videos are about how cool the photographer is to be getting this but the videos have no contextual information for you the user. They're just cool and the guy making the video wants you to know he's a cool guy.
