It's a term that you mostly find in government circles, media reporting and advertising. Outside of these, it is a warning sign that a person comes from that background and has not much down-to-earth experience with security topics and/or is trying to sell you something. (At least that is my impression from reading various discussions about the word)

A lot of my fellow security analysts have an irrational dislike of the term cyber. Personally, I'm indifferent towards the word. When someone uses it, I know exactly what they are talking about. Isn't that the important thing?

It is increasingly used in situations that have pejorative connotations, "cybersex", "cybercrime", et cetera.

I thought cyber meant systems, like cybernetics.

Cyber means to steer and cybernetics is self-steering systems based on feedback and goes back to Norbert Wiener in the the 1940s.