The concern mentioned in the excerpt from TFA was a perception by the people it spoke to that they had to self-censor in order not to be personally attacked in online discussion.
You make a good point but it seems like it is about something other than what the TFA excerpt describes.
TFA quoted by OP:
> participants talked about having to constantly run a cost-benefit analysis on participation in any online conversations, based on the likelihood that they would be attacked, merely for participation.