That is assuming there is a layer above the executive, which is not necessarily the case.
It is true for anything with a board, of course. But there is no rule mandating boards.
Public companies in the US are required to have a board of directors. If they’re not a “controlled company” - i.e. no single person controls more than 50% - then a majority of the board are required to be independent, i.e. not employees, executives, or consultants to the company.
Pretty sure all publicly traded companies in the US are required to have a board