I grew up in Yorkshire, though I'm half-Scottish there's no link to Dundee!
But the Spectrums were the best-selling UK machine at the time, so I'm sure there were lots of regions where they were super-common.
I think I had a friend with a BBC Micro, but I can't recall anybody else having something different.
(There was a bit of console-split later, between NES and Sega Megadrive, and later still between Atari/Amiga, before we all settled for big grey boxed PCs.)