Do not recommend channel doesnt work. It only pauses recommendations for a few weeks. I've selected do not recommend on channels several times and they still sneak back in.
I have a dedicated Chrome profile/account for watching videos that I don't want infecting my primary account's recommendations. Right click, "Open link as".
This is weird to me. I've banned a bunch of channels and never seen them again. You're not just doing the "I'm not interested" thing, right?
I've heard this from a couple other people, though, which makes me wonder if the alleged "don't recommend channel" button is hooked up to different API calls in different UIs...
At least in the YouTube app on my Android phone, on the main suggestion feed, there's another option on the same 3-dot menu that is specifically labeled "Don't recommend channel". If you don't see it right there, maybe dig around.
Just checked, and I don't see it in the suggestions under a particular video, only on the main feed. I don't know if they're hiding it or what.
It's one of the very few things that actually work