The Wiki article makes it hard to feel bad for this guy.
How about we stop justifying hurting people because of their (in this case retroactive) violations of social/political norms and worry more about if our society itself is tolerable and is, in fact, sometimes perfectly deserving of extreme reactions.
But really you're not confused at all, you're just trying to bait me into a tedious semantic argument in which you'll suddenly forget how English works and what words even mean, and I'm not wasting my time with that.
If the "they" are the people supporting the punishment and torture of someone for reporting on corporate incompetence, and the manner of punishment is extremism, then your rationale leads to the extremism you want to punish. By this rationale, society deserves the extremism it gives rise to through its treatment of individuals who were not extremist before the treatment.
It's a terrible rationale. The extremist ideology, itself, is unjustifiable regardless of the means by which it's acquired.