Just think back to when you were only 15. If someone told you then half of what has actually happened since, you would think they'd read too many sci-fi comics
When I was 15 there weren't many (if any) sci-fi comics, though sci-fi books were common. But not everything today would be a complete surprise to one who'd read Heinlein- his
Space Cadet, for example, had what were essentially cell phones**, his
The Moon Is A Harsh Mistress had a computer that came to "life," much smarter than today's so-called AI, and that's just one far sighted author and only a couple of items in a couple of his novels. And a few early movies, such as
Forbidden Planet, had some interesting thoughts too.
Still, your point is well-taken since so few (comparatively) folks back then read sci-fi or gave much thought to an actual future such as we have experienced.
Curiously I had an interesting conversation many years back that's a bit related: In the late '70s a friend and I each got a TRS-80, and we messed around with learning Basic and machine language, as well as digging into the innards, functionally speaking. One day he and I were at our kitchen table chatting about the future of computers and we postulated that one day there'd be computers with color, much higher resolution and much more that would describe typical computers of the '90s. DW scoffed at this, saying it wasn't possible. By the late '80s she'd seen the Amiga and the earl;y PCs and admitted she'd been very surprised when this all actually happened.
**
From Wikipedia:
The novel contains an early description of a
mobile phone:
Matt dug a candy bar out of his pouch, split it and gave half to Jarman, who accepted it gratefully. "You're a pal, Matt, I've been living on my own fat ever since breakfast -- and that's risky. Say, your telephone is sounding."Oh!" Matt fumbled in his pouch and got out his phone. "Hello?"
The phone "was limited by its short range to the neighborhood of an earth-side [i.e. terrestrial] relay office". A cadet avoids having to talk to his family while traveling by packing his phone in luggage.