In University. In the 90s we used commercial un*x (HP-UX, IRIX, AIX, Solaris/SunOS, SCO) and some others like SVR4, BSD, Minix. Then a guy on usenet talked about making is own kernel running on a 386. My first real full linux install was kernel 0.99 on a 486DX50, around 1993, came in multiple floppies, then to install X11 that was like 10 more floppies! Configuring things was a bit nighmarish.
Yes, at least seeing a 50yo guy like me. We come from the 8bit world, there was no linux!