They think being able to Google/SO something is the same as knowing it. Give them a laptop without internet access and most 'developers' wouldn't even be able to get it setup nevermind write 'hello world' from scratch.
In some ways, it's like the transition between oral history and written history. Both were ways of storing knowledge, but one was far far easier for more folks to access.
Of course, as a dev, it's also important to be able to experiment and test, and the internet has changed that by making computing power easier to access (whether heroku, cloud providers, or even just things like requestbin).
And I didn't know many programmers. Computers were expensive and so was the software and reference books. I was lucky enough to be able to afford these things.
Also, everything was just slower before the internet. At the rate things change now-- it doesn't make sense to publish books about most programming topics that change much faster than than a book could possibly be published.
The internet also changed computing in general because, that's when computers started working against us (the beginning of surveillance capitalism).