The founding generation was particularly wary of vesting too much authority in a single individual. After all, it just fought a bloody war to free itself from the tyranny of a king. https://tenthamendmentcenter.com/2020/06/30/executive-power-who-made-presidents-and-governors-kings/

So, most of what is on the books today.

As you may know, the primary “constitutional” justification for our out-of-control administrative state is a grossly bloated version of the Constitution’s Commerce Power. In a case pending before the Supreme Court, apologists for centralized authority want the justices to expand that power even more. https://tenthamendmentcenter.com/2022/09/12/will-the-supreme-court-stretch-the-commerce-clause-even-more/