You're alluding back to the moderation problem. I claimed that discerning between pros and wackos is turing complete, and you have indeed shown that discerning between ANY kind of allowable content A and disallowed content B is also turing complete - you can get arbitrarily close to the line between A and B, so any algorithm (or human guidelines) is necessarily going to have issues on some edge cases.
I agree, you're absolutely right. Still, I claim it should be done, and maybe the content you listed should also be disallowed.
I'm not saying these videos and discussions shouldn't exist, I'm suggesting that perhaps it's time we dispelled the idea of a global Town Square - one platform for all content. It's a recipe for disaster. We've seen what can happen and what will continue to happen. Facebook, Twitter, YouTube - how many times do we have to watch a global town square devolve into shit flinging, disinformation, and hate?
Let's stop pretending that there can be a global free speech forum and that we can have some fair minimum ruleset to moderate all content on that forum.
We should opt for the opposite - a spectrum of platforms that appeal to different interests and are regulated in proportion to the severity of incorrect or bad-faith information in that interest.
The entertainment that dominates Youtube is minimally severe if incorrect or bad faith, so YouTube would have minimal regulation.
Content on personal health and experiences could go into HealthTube, where moderation exists to prevent making strong medical claims or pushing bullshit (the "pay an influencer to say that ElaMexaTrin cured my covid" problem), but people are otherwise allowed to post what they want about their personal experiences.
Content with strong scientific claims on health would go into MedicalTube, which is regulated and heavily moderated to prevent commercial interests and disinformation.
Really, if YouTube was forward thinking, all of these could be different subsets of the same platform. But instead we have one platform with the same erratic hand of moderation slapping things down left and right based on whatever changing ruleset seems convenient today.