I’ve mentioned this type of thing before. For example, DIY has some issues like that where having a canonical Q/A/“thing” o some type would answer a boatload of questions if people could find it easily. With regular Q&A they have to search and newbies don’t know what to look for.
This sounds like it might run afoul of the problem SE has had with tag wikis and Documentation. Tag wikis aren’t visible enough, of course, but very few of them got enough creative attention to be useful for this kind of post.
Documentation had a number of unforced design errors, but AFAICT it didn’t have enough focus on requiring topical expertise, so it never bootstrapped into a self-correcting system; many sections were ignored, others were filled and checked only by the ignorant. The high-level layout concepts were a little vague as well. A better privilege system and a more coherent initial design vision would help those a good deal, as well as the obvious fact that Codidact is not likely to have the massive userbase of eager rep-hunting ignoramuses, even for years after MVP.
I like the idea of a blog-style post that sits right there alongside questions – they show up in the question list, and they have tags so they’re discoverable that way too. To keep things focused, a post of this sort should have a problem statement as a title. “Everything you need to know about database design” is a bad fit for a blog post; “preventing SQL injection and why it matters” is a good fit.