"This issue is a lot more complicated than most people understand," Abdo said.
"On the one hand Facebook has an absolute right to kick these people off of its platform and the vile speech in which they engage causes harm in the real world. On the other hand there's a risk that Facebook embracing the power to decide who gets to speak and who doesn't get to speak in the largest online discourse ever constructed is a dangerous proposition.
"The idea that a single company will decide these questions will create a risk that others whose opinions we value more than say Alex Jones will also get silenced."
Decried as censorship by several of those who got the ax, the move signals a renewed effort by the social media giant to remove people and groups promoting objectionable material such as hate, racism and anti-Semitism.
"There's also the risk though that the focus on these episodic spectacular instances of censorship by Facebook distracts from what may be a more significant form of content moderation that Facebook engages in every day," Abdo said.
"And that is the decision they make every time you open your Facebook feed to show you some content and not other content. This algorithmic prioritisation is a much more significant form of content moderation that Facebook engages in.
"But we know relatively little about it. And yet it may ultimately decide who gets seen and who doesn't get seen online."
Facebook has previously suspended Jones from its flagship service temporarily; this suspension is permanent and includes Instagram.
Twitter has also banned Loomer, Jones and Yiannopoulos, though Farrakhan, the leader of the Nation of Islam long known for provocative comments widely considered anti-Semitic, still had an account Thursday. So did Watson, who rose to popularity as editor-at-large at Infowars and has nearly a million followers on the site.
"Alex Jones is not influential in our society because he's persuasive. He's influential because Facebook's algorithms have decided to propagate his views widely on the basis of their design to promote user engagement. And that decision that Facebook has made to improve or amplify voices that promote engagement results in voices like Alex Jones's being being spread so widely," Abdo said.
Facebook said the newly banned accounts violated its policy against dangerous individuals and organisations.
- AP