The fact that Google is ceding the fight against toxic comments on YouTube is actually pretty shocking. In a company that knows more about you than you can possibly imagine, and more about automated sentiment analysis than anyone in the world, they couldn’t algorithmically determine who should be allowed to post on certain subsets of videos, or devise a system they thought was worth deploying to ensure comments meet…
In reality, if they wanted to fix comments, they could easily do it without any high-tech stuff, through basic UI redesign.
It's the quintessential broken window effect. The comment section design is horrible for actual discussions. People who have something intelligent to day simply don't bother. On the other hand, anyone who wants a place to put some hostile nonsense with high visibility gets exactly that. The behavior gets normalized and the ratio of hostile nonsense keeps itself at a high level.