This kind of problem isn't just because of search, it's also because of content creators. I believe what all content creators quickly learn is, on any given topic, the funnel is extremely wide on the most introductory knowledge and then becomes uselessly narrow as you drill into specific info.
To use a specific example, the other day I was trying to learn more about programming shaders. There is an unending number of basic level tutorials: what is a shader? There are probably 500,000 people searching for that topic. But if I want to figure out a UV scrolling texture, I'm screwed, there's almost nothing. Because the audience for that is maybe 500 people.
There's just no financial (or even reputational!) incentive for anyone to write an article / make a video on something requiring deeper expertise. There is stuff out there, of course, created by the tiny minority of passionate enthusiasts or dedicated professionals. Google is really searching for a needle in a very, very large haystack. And I think Google (and other search) has been more and more challenged by that over the years as the internet moved from a niche enthusiast place to a mass market place. Particularly when all the hay is spending massive amounts of effort on trying to pretend to be a needle.
tl;dr I despise using Google (or DuckDuckGo) these days but I don't think all the blame should be assigned to the engines, they're actually facing a tough problem. (Not that you personally were saying that, but this is mainly a thread of hating on Google.)