[chipsrafferty]

Unfortunately, it doesn't really work like that. If you say "Don't recommend channel", the channel may in fact be recommended and similar channels will definitely still be recommended. "Not interested" works even less accurately.

[karmakaze]

IME, Not interested at least prevents that single video from showing in my feed. It may reduce similar content from same or other channels--I see some reductions. Don't recommend channel always works for me as far as I noticed, except in search results which seems correct. I never expected it to not recommend similar channels, e.g. I filtered out Linus Tech Tips but watch similar content.

It probably helps that I only permit a handful of specific topics: physics, fun math, synthesizers (but not modular), tiny bit of music theory/training, StarCraft 2 (not SC1/BW), and recently the Nvidia/AMD GPU release saga.