I do not think they are too valuable anymore as references you keep coming back to, that use-case has been long superseded by the internet, well before AI. But for a novice learning programming, I still believe that there's absolutely no substitute to reading a book from cover to cover.

I have seen a myriad examples of people that have half-learned a language from random snippets in the web (or from AI now), and the struggle never ends. And taught courses or videos tend to be too time-inefficient and too shallow, more of an intro.

A good book is still by far the best way to get the complete and cohesive overview of a technology and put it into context. It gives you the kind of mental model that allows you to solve fresh problems from first principles thinking, because you understand the whole breadth and depth of how the technology works.