That's a pretty weird view, like arguing that a Dean of a science department ultimately gets credit for any important scientific advances his professors make, because he's ultimately responsible for the department's success as a scientific research institution, staffing, funding, construction of buildings, intellectual climate, promotion and compensation policies, etc., all of which are necessary for the research to take place and influence what kind of research is done.
CEOs, and Deans, do of course have influence on success, but I don't think a blanket, "all credit goes to the man on the top" makes any sense. One needs to investigate the extent to which different people actually contributed, i.e. whose contributions were minor, moderate, necessary, etc. Some executives of successful companies deserve a lot of the credit; others don't; depending on why the company succeeded, and what they or other people did.
And if you want to take a real capitalist-agency view, the CEO is merely another employee, and ultimately the owners are responsible for success or failure.