More to it
I get your main point that young people are fairly tech savvy when it comes to newer technologies like WiFi. But this is not strictly a "culture change" issue. Your hypothesis is things are better and faster than old tightly controlled days. I would argue the opposite. In this era of cheap and fast, no one, particularly governments like you work for, can even remotely guarantee that data they possess will stay in their hands, not some hacker on other side of the world. When we were mainframe centric, with tightly controlled access, was that a problem?
Now, I'm as far from a security guy as you can get, my job is development. But certain things make sense. Like your example in hospital. You really think that access to records should be left wide open? I'm sure what your suggesting is use biometric or something to make it easier on busy doctors/nurses. But you know that is a cost issue.
Printer example also highly over simplified unless you are talking about USB attached local printer. You really thing these kids can self serve to get a fixed IP, install drivers and queue on print servers? If you are a company like Spotify, then you probably can operate much differently than GE. Or my Mfg company. But to suggest the GE's of the world can operate willy nilly, BYOD, solve your own IT problems is way too simplistic for today.