Only in Spain there are 3k publishers. Argentina has 1k publishers.

And then we have huge amount of books published in spanish by Penguin Random House, Scholastic, Springer, etc.

In the section for my native tongue, I zoomed in a few times, here and there, and I only once did I stumble upon an author I knew.

To me, writing a book feels like such a monumental endeavor that I find it hard to fathom the amount of collective effort that it took to write all this, especially considering how most of these works are almost forgotten by now (something something power law).

There's nothing AA could "fix" here, this depends entirely on volunteers uploading the books. Your best way to help is to buy the books yourself, use a book scanning service (eg. 1dollarscan), and upload it to ZLib/LibGen.

You can also make a book request on ZLib, that way someone else will be able to do that for you if they want to

With a few other options in search:

https://openlibrary.org/search?q=%22steel+construction%22&mo...