As a relatively elder millennial (1987), I'd concede the title of last true pre-internet generation to Gen X. My family got AOL dial-up when I was in 6th grade, which was a little behind the curve compared to my peers, but not much. So I certainly lived through a seminal transition period as the internet developed and became...what it is today.
But the hallmark experiences of the pre-internet times, payphones, paper maps, coordinating with others, I only did so in my limited capacity as a child. I had a cell phone by...10th grade, I could at least print out MapQuest directions, etc.
I remember a lot, but didn't truly interact with most of it.