I think the point is that "pissing off" radicals is more cathartic than useful. What moderate people want is to thwart their ambitions, but ideally de-radicalize them so that they are no longer dangerous people in need of thwarting. The main argument I see against a move like this is that it may temporarily achieve the former but only at the expense of the latter.
Personally, I believe that de-platforming is a useful tool when radicalization is spreading like a contagion, but only if it is applied in a consistent way and with well defined boundaries.
Radicalization is the process feeding someone an explanation for feelings they already have. We have to address the root cause. For a huge segment of people the root cause is the hollowing out of the middle class over the last 50 years. We're completely incapable of solving this problem with the same economic tools we've been using.
Taking away communication kicks the can down the road in the same way.
> For a huge segment of people the root cause is the hollowing out of the middle class over the last 50 years.
I keep hearing this, but the data shows a different story. Trump supporters (and Republicans) in general are wealthier than Democrats, and the country as a whole.
Personally, I believe that de-platforming is a useful tool when radicalization is spreading like a contagion, but only if it is applied in a consistent way and with well defined boundaries.