I should've selected the example more carefully. If the first few seconds of the video is of a 13 year old, then the app can probably safely be discarded, so it's still a decent low-quality filter.
Also, if you put "almost zero" effort into your intro video, then it's going to suck. I don't know what YC is looking for in the video, but it seems like you'll have a higher chance of them funding you if they see that you have at least one naturally-charismatic founder, in addition to a very skilled technical one. The video can show your charisma, just like the application can show your technical skill.
It still seems like the total number of fully-completed applications will decrease because of the video. But again, that's a good thing.
Also, if you put "almost zero" effort into your intro video, then it's going to suck. I don't know what YC is looking for in the video, but it seems like you'll have a higher chance of them funding you if they see that you have at least one naturally-charismatic founder, in addition to a very skilled technical one. The video can show your charisma, just like the application can show your technical skill.
It still seems like the total number of fully-completed applications will decrease because of the video. But again, that's a good thing.