They could probably infer that if I'm watching comedy,and the last 5 videos were comedy by the same artist, I don't want to watch some guy's channel about bassists that they've tried to get me to watch 100 times prior.
I'd take your point if they only recommended bass videos, but presumably it's just one recommendation in a list of many, with the point being to explore your preferences while also satisfying your demands
davie504 is basically a musically-themed comedy act, so this doesn't seem that unreasonable.
Other than that, I'm pretty happy with my recommends. I think the Google spooks have built a good file on me.
https://addons.mozilla.org/en-US/firefox/addon/youtube-clean...