Yes and no. The official documentation can be obtuse and bad for new learners. (I'm looking at you, gradle[1]). Ideally, the official documentation includes tutorials, but also three other forms: 1) how-to guides showing the steps for accomplishing a common goal. Think of them as extended FAQ answers. 2) simple reference docs. Your typical api-centered doc, or man page cli flag list. Answers the question of "what was the function/class/flag to do that?" Assumes you already know how. 3) explanations, the discursive articles about how and why. A lot of people can get by with never reading these, but once in a while they can clear up some problem you're having. The tutorials, which should exist, would be short guides for learning by doing. They aren't how-to guides, because they don't assume you know anything yet. They are often the best entry points for picking up something entirely new.
[1] https://www.bruceeckel.com/2021/01/02/the-problem-with-gradl... and https://melix.github.io/blog/2021/01/the-problem-with-gradle...
But we've all seen the reverse, as well, and a combination of SO, YouTube, Reddit, and random tutorials is the only way to figure it out. Especially when you encounter the "This describes version 3.1, and everything in 4.5 is completely different, good luck" official docs.
There are definitely cases where the official docs (or RFCs) are practically incomprehensible to a newcomer, but I usually will try and come back to them quickly after getting a foothold using a blog post or YouTube video.
I find that even with the best technical writeups, there are often things applicable to MY use case that may not have been relevant to the author. The official docs (or sometimes the source) is the best place to find out about those.
A) Reading a manual requires some requisite knowledge due to esoteric references.
B) RTFM is a skill in and of itself.
C) Manuals rarely mention corner cases or "gotchas" which can cause confusion to a beginner.
D) Manuals never comment on best practices, which tutorials do.
Not necessarily the right approach for beginners, but I've wasted a lot of time trying to find the thing in the documentation, when I should have just lifted the hood in the first place.
Edit: I actually just made up (as far as I know) UTFM, but I really wish it were a thing.
So unofficial tutorials do have their place in introducing design patterns or listing trade offs between different approaches. But I do agree the source of truth should still be the official docs.