A pretty common sentiment is that you neuter trolls when you remove any chance for anonymity, i.e., you put their reputation on the line. I would be happy to belong to a "free speech-oriented zone" on the internet that required real-life verification. Then people wouldn't be so quick to spread virulent, violent ideologies in such a space. IMO this provides a secondary effect, namely that people would stop taking so seriously those areas where anonymity is provided. Perhaps the interactions can be strongly weighted toward local ones, to provide more accountability. Such a platform would need to be free from any sort of money transactions, especially Facebook's current business model.
Furthermore, empathy has nothing to do with advocacy. The ingredient missing when comparing refugees with white nationalists is that of the fundamental power imbalance. One is certainly free to express empathy for both, but tuning the narrative to equivocate people who are being exterminated with their exterminators is pretty dishonest. Your moral obligation (imo) when presented with people who are being systematically denied requirements for life is to spread and advocate for their survival. Notice that white nationalists are only being challenged on the lines of "liberty" whereas refugees are being challenged on the lines of "life." The DoI says it best, and puts them in a specific order not haphazardly, but deliberately: life comes first (and thus the removal of threats to it), then liberty, then the pursuit of happiness.