One user-generated solution that’s helped in this regard is what I privately call “reference topics”. A good example is one about guillotine imagery.
For years, topics would be de-railed by the same old hand-wringing about Cory’s and others’ use of guillotine imagery, falsely and often disingenuously and repeatedly claiming it was prescriptive rather than admonitory. Since the topic was established, I’ve referred anyone who starts up with the guillotines to it. There they can see their “brilliant and unique insight” has been expressed (and usually de-bunked) many times before, going back years.
On the same note, this has become a “reference topic” of late.
This topic on free speech serves a similar purpose when someone once again mistakenly or deliberately misconstrues how the First Amendment works.
I also used to preemptively refer certain people in mass shooting topics to this mod note to try and keep them from de-railing with wankery about the technical details of weapons:
I’m sure others can point out further examples. Of course, the site rules FAQ is the ultimate “reference topic”.
@ClutchLinkey above started getting at how Discourse and/or BB might modify things to make user-created “reference topics” a more formal category. Perhaps not auto-closing them would help, for example. Or allowing the mods and/or leaders to designate a user-created topic as a “reference” one.
If this happened, I’d be interested to know if it would be OK for leaders to move an Off-Topic but still interesting discussion sub-thread from a Topic to one of these Reference Topics as appropriate.