Right, but all of the above are very conscious decisions on each company's part.

> "On Facebook you're interacting mostly with people you know, at least tangentially and who are identifiable as individuals to you."

But also importantly, Facebook gives users control over who is allowed to see your posts, message you, or reply to your posts. They started with a default-public model and have slowly contracted this to favor those you have explicitly friended over rando strangers.

This is a conscious decision on their part from their learnings about abuse - it isn't accidental.

> "You're welcoming comments from anyone and in large part the abuse comes from arguments arising from discussions of controversial topics"

It does, and many of Twitter's mechanisms make this phenomenon worse, at no benefit to users. Someone says something controversial, and that person's followers get into an argument with them about it. And then someone retweets it and yanks in a completely different group of people, none of whom know the original poster, or in fact know anyone (even obliquely) involved in the conversation.

And then someone else retweets it into another group which is now even further removed from the original conversation. At each level empathy decreases as outrage increases, and at no point was there ever a helpful discourse for anyone.

Fast forward an hour or two and somebody is calling a SWAT team to somebody else's house.

Twitter is fundamentally structured in a way that allows a very high branching factor to content dissemination. This was a great way to gain traction early on, but at this point IMO is more a liability than a strength.

Twitter's also consistently refused to assign explicit ownership of spaces. On Facebook if I behave abusively in one of your posts, you are free to delete my post. I can also control who sees my posts and who is allowed to reply to them.

No such control exists on Twitter, where anyone can butt into any conversation at will, and none of the original participants in the conversation can do anything about it - because despite being the original participants no concept of content ownership exists.

> "These tools inherently attract a different crowd. In terms of both use and abuse."

That's exactly my point. We tend to think of abuse mitigation as a purely reactive topic - someone is abusive, another person hits the "report" button, some system kicks in, posts get deleted, people get banned, etc etc.

But that's a losing battle. You can't outpace reactive abuse patrol/flagging if the structure of your tools, like you said, inherently attracts a different crowd. The fundamental designs of our social networks (or really, all technology) needs to account for bad actors. Abuse prevention cannot successfully be implemented as a layer on top of something else.

That said, I think it's also an error state that these services attract a "different crowd". Human behavior is incredibly circumstance based - people will behave as the system encourages or discourages. I'm willing to bet that nearly everyone on Twitter is also on Facebook, but they act very differently on the two services. It's too simplistic to model abusive bad actors as inherently prone to abuse.