My first job interview in 1989 after college:
Them: "Do you know TCP/IP?". Me: "Yes". Them: "you're hired"
Job at the Westinghouse instrumenting nuclear power plants. Simpler times then.
Same for me in 2006 as a junior Linux sysadmin:
“What does ifconfig do? What does it mean to mount a disk? What editor do you use? You’re hired.”
None of that culture fit nonsense.
Back in 1989 that was a rare skill. Many of the engineers who had experience were working on government projects. I mean TCP barely had congestion control at that point, it was very early days.