This mod action wasn't just intelligent, it was actually harm reduction.
It's a known thing that folks with ADHD may engage in internet arguments for the dopamine. Divide by Zero has a number of neurologically atypical members, and while we're a self-governing herd of cats (the majority of which seem to have level heads), we can't always stop engaging in stupid, needless, dumbass arguments when we should. Especially when mixed with people of... differing ideology.
The comments section was allowed to mature enough that a majority of people weighed in on the original point of the post, the mod action, before it devolved into arguments about the content of the post being actioned. That's the perfect age for locking the thread.
An analogy- the pirates were allowed to get into and distribute the rum. They were allowed to drink and sing. When they started fighting, that's when the cat o' nine came out. This is appropriate and about the only way to run a ship.
ETA: I hope you all know how fucking difficult it was for me to approve of someone in a position of authority in public like this. I'm real glad there's zero ties to this account and anything to do with my real life because I have a fucking reputation, thankyouverymuch.