Admirable move. I think Facebook (and all its properties), Twitter, and other hyper-connected social networks must show a healthy level of intolerance towards groups and ideologies that are beyond reason and recall, especially when those said groups are overtly and unmistakably intolerant themselves. This heavy-handedness isn't an encroachment on free speech but a necessary impediment to keep the spirit of free speec…
And how can anyone call themselves an adult if they need some third party to come in and censor things for them? You can block, you can mute. You can stick to trusted groups. You can also learn self control and not feed the trolls.
If we want to control intolerance effort should be put into making the systems by which we personally and purposely block it from our lives more robust. And if they're going to try to create a universal bubble, it should at least be possible to leave it.