I'm not part of YC so take this with a grain of salt, but I don't think that not viewing videos is necessarily a bad sign based on comments I've seen from the YC founders about the subject. Videos are mainly viewed to see the chemistry between founders. Someone posted on HN the other day who said that last batch their video had 2 views and they got an interview. As long as your written application has all the relevant info, I wouldn't worry about this stuff.