Back in the 90s, Macs were mostly used by the "tech nerds". Normal people ran windows 95/98. It's still kind of weird to me that Macs became sufficiently mainstream as to lose their tech nerd cred :)
My own experience was learning on an old IBM PC at school, then Apple 2s later. Also my dad was a programmer (but maybe less nerdy/more professional) so I got second hand x86 hardware and learned to program on Windows with Visual Basic, Delphi and Visual C++ (since he already had licenses). Eventually I got into Linux in the late 90's.