You're not wrong. You're 100% right. This is like posting a story about how a game engine works, and having it be just blocks of assembly language with no explanation other than "here's some code multiplying a matrix, and then...".
Problem is that such a work would probably have to be more of a textbook, in terms of length and impenetrability. And it's not immediately obvious who the audience would be, as the vast majority of game developers these days are using pre-existing engines, rather than building new ones. But maybe there's still enough conceptual underpinnings that are worth discussing which would still be relevant for Unity/Unreal/Godot folks.
It doesn't always have to be a choice between writing a book and nothing at all because the topic is too complex. I personally have benefited from bird's eye view blog posts and mini-articles more than I can remember. If you have the knowledge then go for it, someone out there will thank you.
When it comes to the 3d renderer alone, there's at least enough common ground to explain the big ideas. Like "we multiply matrices because GPUs can do that very well in parallel and we describe our geometry as points because we can then describe the whole image using simple coordinate transformations which boil down to matrix multiplications."
I feel like a comprehensive article would need to be more of a catalog of "here are the basics of the various major approaches and how they differ and why you might choose one over another", rather than (for example) advocating specifically for forward shading vs. deferred vs. forward+ vs. clustered as being the universally "best" option. (especially when that whole discussion has become kind of moot for the majority of modern games developers, who mostly just take their engine's default rendering pipeline and just use it)