Maybe nothing to do with this book, however; I think the difference is more obvious between early programmers in the 70's/80's and maybe a part of the 90s and the programmers who learned it after that and 'just' do it for the money. The latter can still be excellent and love programming and the science, but they miss that click of what a amazing machine they actually have in front of them. People who have that overwhelming feeling, and I know many of them, see the machine as the most versatile thing in the world in which you can do anything with code; make money, yes, but create worlds, make people happy, make yourself happy, solve puzzles etc. Most of these people don't have time or the inclination to pay attention to clothes, act social (outside the people who understand) and hit the gym. Mostly because everything is possible within the computer and there is enough possibility in 1 80's machine to fill 100 life-times with joy and wonder. I wrote my first program in '82 and I have stuff to do, problems to solve, software to write, infinitely more interesting to me than what I can think of outside this realm. If I plan my biggest project objectively which I now am working on for around 17 years, I get to about 400 man-years of work to do. But I count on more brilliant folks than me helping by inventing shortcuts / faster computers. And that's only 1 of the projects.
I have always been a social animal, I did a lot of sports, I have always started and ran companies with employees and I did go to clubs. I have always regretted that; I wish I could just only spend time on this marvellous apparatus; doing it all over, I would do.