I see more of your latter paragraph. In several of my interest areas there is a good amount of useful content in videos. Best example is probably electronics, where a lot of tribal knowledge is now more accessible than ever before. Practical mechanics, both old fashioned (metal and woodworking) and new (CAD design, 3d-printing), also has a lot of useful video content. While there is a lot of pop-commercial "personas" making noise with their videos also, it does not seem to have hurt output by "in it for the passion" people.