Most lectures I've attended are not interactive except for a questions and answer session at the end perhaps. In a live setting there are breaks and periods of silence too, people take time to look for notes or write on a board or demonstate something in silence and no one sees the need to fill that time with noise.
What one considers "doing it properly" and concluding that doing so makes a video better, is subjective at best. I've seen many video tutorials on Youtube where the majority of comments are lower the music, kiill the music, change the music, etc. Trends come and go, and this is obviously the current trend, so I suspect I better get used to it.
In the end though, I can only speak for myself, and as in this case I'd prefer silence over the repetative noise. I've done video tutorials many times and never once has anyone told me I should add music or some background noise, but i do tend to be verbose.
But as the saying goes, to each is own. So we'll just have to agree to disagree peacefully on this one.