The forum is a place for education. Leaving bad faith questions up hurts that goal and there aren't many practical alternatives, especially given the massive asymmetry in effort by contributors. Did you know that posts often take multiple hours to write? It would only take a couple dozen malicious posters to completely overwhelm the relatively small contributor base without mod intervention.
This is true if and only if there is sufficient bandwidth to process all those ideas AND the actors are all people who are trying to learn/seek truth.
Expertise and conversation time is limited, and it's considerably cheaper to ask questions and sow doubt than it is to fully address those questions. Given that asymmetry, it feels more than reasonable to accept certain things as ground truth and eliminate time wasted on dealing with trolls.
I can easily imagine situations where that's not true; besides that, you'd have to admit that people being convinced of bad (and potentially deadly ideas, e.g. anti-vaccination) will happen for some period of time. This concept of "more ideas" is time-based, it relies on the hypothesis that things work out to "the truth" in the end. I don't think that's the case much of the time, and I can see why people don't like the idea of holding that hope for some statements.
There is reason to believe that some authorities - such as scientific ones and even judicial ones, do a better job of finding truth than other venues of discussion. I think AskHistorians desires to be a microcosm of that.
There is an excellent paper by Fred Schauer about the "search for truth" defence of free speech, and how it relates to time[0].
[0] "Free Speech, the Search for Truth, and the Problem of Collective Knowledge" (2017): https://scholar.smu.edu/cgi/viewcontent.cgi?article=4682&con...
Every time in history that we've institutionalized suppressing speech in support of official truth, it has gone horribly wrong.
The problem with nuanced issues like this is that there isn't really a "right" or "wrong" answer, there's just bad and less bad.
You are suggesting that our liberal approach to free speech has failed so we might as well go full authoritarian and shut down the crazy… all to prevent another tide of nazi authoritarianism?
That is hilariously contradictory.
At issue here is a fundamental problem that humans have been struggling with since recorded history, who decides what's true?
When we have demonstrated bad actors at every level of discussion, from authoritative sources down to internet trolls - how do we identify truth, especially with all of it's nuance, without degeneration into a Ministry of Truth, and punishing dissent?
While I understand that the constant battle against misinformation and disinformation is exhausting, isn't that what you're signing up for by engaging in a medium that encourages discussion?
If you don't want discussion and contrasting viewpoints, perhaps you're better served by publishing a blog, or a book, or academic paper where discussion is much slower and involves published responses?
Edit: the irony of a comment like this being downvoted isn't lost on me. That's ok, I knew when I wrote it that it would be.