How does a modern president's role as chief economic planner differ from the role taken by presidents 100 years ago?

Today presidents direct and oversee their cabinet and divert resources to various departments, agencies, and private organizations. 100 years ago, mega corporations from the 19th century still existed and presidents like Teddy Roosevelt had to use "big stick politics" to bend economic powerhouses such as JP Morgan and the Rockefellers. Presidents nowadays have more freedom to control the economy to their whim, for better or worst.