TL;DR: The problem isn't that SE doesn't have these things, it's that people don't read them...
...and then get cross when others point out that their post is off-topic, has already been answered, and that they should've read the basics in the tour, help center, and the on-topic page.
I remember when I asked my first few question on SO: it was closed as off-topic, and after some reflection, I agreed. I've asked some duplicate questions here and site-specific questions in the wrong place. Since then, I've tried to learn from what the site and its longtime users tell me.
Another thing: You're asking for features that already exist. Stack Overflow has The Ask Wizard, a step-by-step approach to asking a programming question. It features forms for helping you choose tags, preventing you from (hopefully) asking a question that has already been asked; it has links to the On-topic page to help you avoid asking a question irrelevant to the site and will alert you if it thinks a solution is already on the site.
Each site's question title also contains a placeholder, like this:
(From Ask Ubuntu). Seems to me that site is for Ubuntu questions only. For those new to a site, a popup will appear containing more information:
(From Academia). I think that part of the problem, for SO especially, is that when new users are in a hurry to get good answers (e.g. for homework) they ignore important guides to asking questions, which leads to downvotes, closure, and complaints about toxicity. As for site-recommendation questions: If you've already done your research and actually read the site tours and still haven't found a solution or place to ask your question, those are welcome here - there's a tag dedicated to them.
I won't lie, I've seen a few snide comments on SO concerning simplicity of a problem or some such. If you see comments like these, don't jump on the "SO is toxic" wagon or lash back; keep cool and just flag them as unfriendly or abusive (depending on the situation). There are plenty of experienced users who won't tolerate condescending behavior and will help.
There were comments on the linked video concerning 10-page on-topic articles, documentation, etc. I would remind y'all that a quick search to avoid duplicates, a read on how to format your question, and a minimal reproducible example will get you a long way. You can find these by clicking on the help icon.
