CEO's do not understand the ROLE that CIO's play. Sure, it would help if the CIO had some business experience, however, most CIO's are TECH's that have grown up into those positions. CIO's understand that the heart and nerve center of every business that uses and utilities IT infrastructures, CEO's don't ... they only care about the bottom line and the profit they generate.
IT runs everything in this world. Water, Electric, Gas supplies, traffic lights, security cameras and so on. If we took a dive back 70-100 years, people wouldn't know how to work or how to act or how to conduct business because IT has made their lives so much easier (yet more complicated).