From the linked opinion piece in the story:
https://www.nytimes.com/2018/03/10/opinion/sunday/youtube-po...
"YouTube leads viewers down a rabbit hole of extremism, while Google racks up the ad sales."
So the big question is, why not demonetize them? Removing all ads probably has a pretty significant impact on the algorithm already.
Why doesn't YouTube do the right thing? Stop making money on extremists? It seems like doing that would auto correct the problems.