I dont see it mentioned BlockTube extension [0] anywhere in the comments yet. It automatically blocks videos/channels based on your defined keywords and it works perfectly. For some period of time my main YT page was filled with a variation of videos about "walking in Tokyo". I'm not interested in walking in cities nor Japan, so I have no idea where that came from. No matter how many of these videos I marked as "not interested", more of them kept coming for days. Blocktube just automatically purged them for me. Sometime I saw just a blank page (because all the videos were blocked automatically), so I had to reload page to see at least something. It took some time to get rid off the "noise", but my YT experience is now way better.