Unix was very expensive at the time of course, meaning only used by big business. I remember asking a computer/IT teacher what it was, in the early 90s. Sounded interesting and somehow we found out about Minix and downloaded it from somewhere to tinker, maybe a BBS?
Luckily this happened, because when I later got an IT job in the mid-nineties at a aerospace company I was good to go. At which point I discovered Linux and then BSD.
Also, engineering-ish small businesses, and universities, and the occasional non-profit saving money with dumb terminals where they'd otherwise need a PC on each desk.
I once paid ~$100 for Coherent (Unix-like) for my '286, then sent it back due to the 64KB process limit, while I used Unix workstations at an internship. My next home computer was to buy a used Sun-3/75 from the local Sun office, for a fraction of a what a PC would cost.
Luckily this happened, because when I later got an IT job in the mid-nineties at a aerospace company I was good to go. At which point I discovered Linux and then BSD.