when their senior leadership often manages their time between the affairs of many companies in their purview

It is kind of tiring for me to read people equating "Elon Musk" with "all those rich guys being CEOs".

When you really are a business owner OFTEN you have to devote 120% of your time and energy for running the company and single one.

People you see on TV flying private jets to expensive holiday destinations are not your average business owners. Elon and the likes are the exception not the norm.