It's probably not that simple. Most chief executives delegate the responsibility of hiring staff to others. Sure, the buck stops with the executive, but ultimately nobody can review every single operational decision at scale. Maybe they hired for a world where the pandemic didn't happen and the monetary supply didn't tighten, then the world changed.
The entire purpose of the C-suite is to stay on top of macro level stuff, and its the boards purpose to make sure the C-suite is doing it. They didn't do their job. And they got rich not doing it.
What CEO doesn't approve overall hiring numbers? If you're worth paying millions upon millions of dollars a year, shouldn't you have capital-F Foresight?
Or is it more that most public-company CEOs are probably not playing above replacement level?