Final answer:
Herbert Hoover, who was a workaholic, managed like a CEO as president, believed strongly in big business, and was both an orphan and a millionaire, is the president described in the question. His lack of direct relief during the Great Depression was seen as insensitive and reflected his philosophy of 'American individualism.'
Step-by-step explanation:
The president in question who had a tendency toward melancholy, managed like a CEO, was a millionaire, was an orphan, believed in big business, was seen as unrelatable, and was a workaholic is Herbert Hoover. Hoover rose from poverty as an orphan to become a successful engineer and millionaire.
His presidency was defined by the philosophy of "American individualism" where he believed in minimal government intervention in business. However, his policies and response to the Great Depression were seen as insensitive to the plight of ordinary Americans.