It was a funny way to refer to the school.
This fell out of favor before the mid 70s and was never heard from for decades.
In the late 2000s, Utah fans picked up on Zoob as an insult to BYU fans. It's stupid and not insulting and makes no sense.
I don't understand why they still use it. It's not clever or a good insult or anything, and nobody is triggered. It just makes them look stupid