It was created in a time when physical restrictions on access to the machine was enough. If you weren't meant to be in the lab, somebody found out real quick.
Wasn't just that, it was everything. DOS, early Windows, etc all didn't give a rat's ass about security. In 1986 you could just go over to your friends house and turn on their machine and just go through all their shit laid bare. I don't even think we had BIOS passwords at the time. At least the machines I used didn't. It was a wild time.