I only would agree with defederating if it’s proven that they are blocking anti-genocide content on other servers from being visible to their users.

In general I believe that maintaining lines of communication with those who otherwise believe in reprehensible ideologies is best, both in order to better understand such backwards ideologies, and also to provide a lifeline back to consensus reality for people who’ve been swept up by them.

I also believe that in the majority of cases, users should wield the power to instance-block for themselves. Or at least, servers where this is the case are the ones I prefer to participate on.

However, if it becomes clear that feddit.org admins are censoring content external to their instance in support of Zionism, then my first objection becomes irrelevant, and the second would be questionable, given the efforts of admins to put external fedi content thru a pro-genocide filter. At that point, defederation would be both warranted and wise.