Wealthy kids have access to toys others don't I knew what a modem was and why I wanted one long before I actually got my hands on one, because I'd seen American teenagers using them in movies, eg War Games in 1983 (which I rewatched recently and was rather surprised to find it still holds up for what it is). Also, there may have been no need to call internationally. When I was into home and later business computers as a teen in the 1980s in Ireland (which was then as economically benighted as SA for quite different reasons) things like porn, bbs software, and lists of 'interesting' phone numbers were circulated on floppy disks; I ran a safe stash out of my school locker because the teachers thought I was too nerdy to be mixed up with the 'delinquent' kids. A single sided 5.25" floppy seemed like oodles of storage space back in those days XD

I don't find this claim so remarkable, though it's certainly possible that the details are fuzzily remembered nearly 30 years later.