My nephews (all under 16) have only experienced "always on" internet. The idea you had to co-ordinate with family on using the phone line via weird screeching noises, only to browse at a slow speed was lost on them.
Not really that unusual - I'm 27 and missed out on dial up
I like to razz my extended family who are all internet addicts now. They told me shit like, "go outside more" but now they are effectively crippled without their devices. Gotta love boomers.