Let’s begin with a very good description of the term System Administrator.
The following description is taken from the book “UNIX Administration Guide for System V” by Rebecca Thomas and Rik Farrow (Pearson PTR; 2 edition, June 1989)
The system administrator is one of the users of a system, and something more. The administrator wears many hats, as knowledgeable user of UNIX commands, as an operator of system hardware, and as a problem solver. The administrator is also called upon to be an arbitrator in human affairs. A multiuser computer is like a vast imaginary space where many people work and utilize the resources found there. The administrator must be the village elder in this space and settle the disputes that may arise with, hopefully, the wisdom of Solomon.
Very well stated and still valid after 20 years!