You can't possibly mean his "Code: The Hidden Language of Computer Hardware and Software" or "The Annotated Turing: A Guided Tour through Alan Turing's Historic Paper on Computability and the Turing Machine"? These books are great.
The Code book I've heard people speak highly off before but have not read it yet myself.
Use a bad metric, get bad results.
Who else remembers this era of giant, unhelpful, rapidly-obsoleted books in the computer section of bookstores? Who remembers bookstores? OK, OK, I've been into Waterstones recently, but it never occurred to me to look at computing related books. What use would they be?
1996 was the beginning of the O'Reilly heyday. If you got a book with a white cover with a coloured bar and animal woodcut on it, there was a good chance of it being helpful. Otherwise it was a lottery - there was a cottage industry of people turning out bad books about software filled with screenshots that mostly replicated the online help.
Spent 45 EUR on this Linux Network Administration handbook by Addison-Wesley Germany as a teenager. Still hurts whenever I think about it.
(Yes, the author also did the screenshot thing: "Look, this is how you configure it using SuSE YaST, and this is how you do it using the Red Hat GUI. Let me show you every single step of the wizard GUI, just to be sure. And this is basically the whole default config file for this daemon, but with "# Created by Bad Tech Writer" prepended. There you go!")
I enjoyed Delphi's performance and recommended it to a customer for that reason, but my own primary motivation was to avoid the terminally cumbersome Windows API.
Borland was already selling version 3 of their compiler by then.
On Windows side, Object Windows Library and Visual Component Library were much more productive, ahead of time Qt, than MFC ever was.
But then Borland's missteps meant that MFC was the only framework left, and only a couple of enterprises still get to enjoy C++ Builder's RAD productivity.
Touché
In '96, LISP (tail end of the AI winter regardless), Perl (half the WWW was Perl), Tcl (maybe a quarter of the WWW and telnet-based services were Tcl), awk, & Ada were quite common, and Smalltalk, RPG, REXX, & PL/1 were at least as common as COBOL. Python was still obscure but gaining ground. PHP had just been released like smallpox on a vulnerable population.
I had a laugh at Delphi being for people who hate Microsoft. Its actual virtue was good performance and safety in large programs, you bought Borland tools because you wanted to double your program's speed, not for ideology.