I can only assume CISO is Chief Information Security Officer? I hadn't seen the acronym before. Bad Zoom for not writing it out in full on the first instance.
"CISO" is a pretty standard acronym. People who don't work in cybersecurity or who don't have that background might not recognize it, but it seems like a minor detail.
Sure, it's a minor detail. And yes, you can say the audience for this post are people who work in cybersecurity. But it costs nothing to introduce the acronym, as is usually recommended. Without it you are alienating anyone who doesn't know the term.
In any case, anyone at the 'C' level almost by definition knows little or nothing about actual computer security.