>>iLoveO+(OP)
Number of videos are less relevant than the total duration of high-quality videos (quality can be approximated on YouTube with metrics such as view and subscriber count). Also, while YouTube videos are not labelled directly, you can extract signal from the title, the captions, and perhaps even the comments. Lastly, many sources online use YouTube to host videos and embed them on their pages, which probably contains more text data that can be used as labels.