As an avid reader (and sometimes writer) of technical books, it's sad to see the, perhaps inevitable, decline of the space. I still remember in the early 2000s Barnes and Noble would still have massive shelf space devoted to every technical topic you could imagine. I could spend hours just exploring what languages and topics there were I didn't even know existed. Powell's Technical Books used to be an entire separate store filled with books on every technical topic imaginable.

The publishing industry veterans I've worked with told me it was even more incredible during the height of the dotcom boom: book sales in the 100,000 copy range was not that rare.

Today I can only think of two truly technical book stores that still exist: The MIT Press Bookstore in Cambridge, MA and Ada Books in Seattle, WA. The latter, while a delightful store, has relegated the true technical book section to the backroom, which unfortunately doesn't seem to get refreshed too often (though, part of the beauty of this is it still has many of the weird old technical books that used to be everywhere).