There was at least one sensible and easy solution: people who crossed from argument (I won't claim there was much debate) into insult could have been switched off for a while with a public reason given. Why not - if one transgresses in public...
Politics is perhaps the most important aspect of public life these days - seems perverse to remove it from the gamut of a "Coffee Corner" slot as if we were all children.
But hey, not my call.
As recently as the 90s (I like to say that's recent

, I was able to have interesting political debates with my friends, colleagues and the occasional stranger, many of whom had completely opposing viewpoints. Often, the viewpoints and stances were well thought out and while the discussions could be raucous, the discussions had some level of substance and even a degree of empathy. Today, to me, most political discussions are simply toxic unless everyone is in the same political tribe. The above discussion, I should say, doesn't particularly seem "toxic" to me, but my own beef with political discussions in a subject-focused forum is they often just take a topic (often not related to politics) down a rabbit hole from which there is no return.
I would love a respite from politics, as others have said, as it causes a lot of noise in today's world. That said, to me, banning political discussion is probably more trouble than it is worth, given human nature. All apes are political, including humans. One approach could be that mods have a remit to keep the threads focused loosely on the stated topic. So you could have politics come in, as it has in this one, but instead of mods saying "politics is banned", they could instead say, "get the thread back on track" if it threatens to completely derail it. Obviously, there is some level of subjectivity as well as using good judgement.
Also, instead of just a generic "coffee corner", add a specific political one, with a warning that the discussions are often toxic. If people get too abusive, they get put into timeout or banned or whatever. Some sites require that any political or religious topics can be read by anyone but only be participated in by people with a certain number of posts, for example. Jeremy would still have his work cut out for him, obviously. But political subjects that threaten to derail one of the main threads could then be shunted off to the political "happy place".
So,
(1) Remove ban on politics
(2) Moderate the threads more from the point of you of keeping them loosely on track rather than chasing political discussions specifically
(3) Provide a place where political talk can happen (I know it was tried unsuccessfully before)
(4) Time-out/ban if too toxic.
It moves politics out to where people can go focus on it if that's of interest to them. Yeah, I get that it's not photography or art or even always interesting. But politics is still going to happen here, simply because over the years it has a long history of doing so, with a not always successful history of stopping it.