Reading the article, the view hinges on a gross mischaracterization: that a free speech environment has led to extremism and death. But this is absolutely not the case. First of all, the websites where the vast majority of extreme ideas are shared are not free speech environments. Second, the people who do bad things do it because they're damaged, or disillusioned, or some other personal motivator, the only difference now is that we can read and understand their view (not implying that we should be sympathetic, only understand even if we vehemently agree).

Another point I have a bit of a gripe with is that the person fails to point out the misdeeds associated with the ideology he (probably) is more sympathetic towards. Interestingly, the view that people should not be able to freely share ideas with one another and judge ideas on their merit with their own cognitive capacity seems to be common among those sympathetic to this ideology. I wonder how the author feels about those people controlling the environments where discussion happens and policing discussion on extreme topics sympathetic to themselves.