>what was reddit supposed to do?

Probably treat the situation the same way they do in other subreddits. The whole “taking matters into our own hands” and calls for violence against politicians happen in other subreddits, and yet they don’t get quarantined (looking at you, r/politics). Either quarantine them all or none of them.

r/politics perma-bans those commenters with a quickness, unless I'm out of date.

Meanwhile, r/LateStageCapitalism, a sub whose premise is to induce lust for the guillotine, has been quarantined before because one user was running around yelling about Guillotines in the comments. This would happen periodically.

So the admins changed up the mod team. They kept the Anarchist/Communist asthetic, but Social Democrats run the sub now. And they keep the space guillotine-free.

If you give me access to their elastic search dB, indexed from the hand of the most honest of men, I will find something in them which will hang him.

Quarantining the community does nothing to mitigate those risks.