> I'm criticizing the design of the site (and to some extent the rules that were set up)

So we agree (but the people you're talking about are not moderators). Again:

>Everyone involved would have loved to "explain this to people gently". There was no space provided in which to do it.

Onward:

> What is it about a bad question that makes answers undesirable until the question itself is fixed?

Many things.

It was partly about working around other missteps of the system design: closed questions that aren't fixed are supposed to get deleted, but the system automating this was deliberately conservative, and in particular would preserve anything that had an answer.

The more bad questions there are, the greater the chance that a third party trying to find a good question with a search engine will find a bad question instead. Sometimes that can be fixed with duplicate linking, but often not.

When a curator believes that a question is a duplicate, and is trying to find the "canonical" version with the best questions and answers, the more bad questions there are, the greater the chance that the curator fails to find that question. This is because bad questions carry a risk of resembling the desired target while actually being about something else.

Answers written for a bad question might be worse because they misunderstand the situation due to the quality issue; and they might be invalidated when the question gets fixed.

Answering bad, low-effort questions contributes to the incorrect impression that effort isn't expected (because the OP gets a reward that might be seen as far more valuable than abstract reputation points: personalized, possibly-working code). It incentivizes more bad questions, when the goal is to preempt bad questions and get people to understand question quality.

Finally, of course, answering bad questions wastes time and effort that could have been spent on better questions.

See also: https://meta.stackoverflow.com/questions/429808

> In fact, people can get more frustrated when a result they consider wildly unreasonable is delivered with a cordial tone.

Right. And the site owners would insist that we adopt that cordial tone, and made multiple attempts to shift the Code of Conduct around in a way that they hoped would lead to more cordial tone.

And people reacting badly to commentary, even when given in a cordial tone, led to people not trying to explain their actions at all. Which led to people being upset that actions were taken without explanation (including in a significant fraction of cases where the system's automatic explanation was perfectly clear enough, frankly).

Seriously: there were many people who came to the meta site after asking a question that literally started with words to the effect of "What do you think is the best...", and then presented as if they could not possibly understand why the question was deemed "opinion-based".