A forum implies discussion to be a goal. Sure, we discuss the site itself on Metas, that’s one of the goals, and why we even have a tag for it here, but that’s it. There’s a big difference between Q/A and forums. Our Q/As (excluding Metas), are supposed to be direct, fluff-free, and with no discussion. That’s the whole point of Q/A. Search for a question, and get the answer, no discussion stuck in your way. So posting Q/As to start a discussion, is an invalid use of the sites.

Maybe you as the post author wants a discussion, but nobody else does. People don’t visit Q/As for discussions, but for answers. That’s why we make them clear and isolated, and why we have strict rules, to maximise their usefulness to later visitors.

I agree completely with the vision. Out of curiosity, do you think the current design lends itself towards that goal?

For example: if a post is downvoted, if we take that as an indicator that the community does not find it accords with the content principles of Codidact, is it sufficiently clear what needs to be changed? Do you think this acts as a sort of "checklist" to determine if a question is good or not, or do we need more information for users as to exactly what they should do in order to improve downvoted posts?

In an idealised world, where the experts always give perfect answers that need no improvement, a Q&A site would be entirely distinct from a forum. In the messy real world, where even experts make mistakes, our Q&A site has comment threads for discussion of how questions and answers can be improved.

Although discussion is not the purpose of Codidact, it is an important part of achieving the goal of clear, concise answers to questions.