The Feds are not one person, and they cannot affect as much as the President. The main board is 12 members, with several others rotating in and out, and by statute they have congressional oversight. The members also have to answer to the regional banks their section oversees, so there is significant checks and balances.

Several of the powers I listed above for the President are absolute (well, up to impeachment, but I doubt any President would be impeached for trade war tanking of the economy.). There are many more powers a President can invoke, such as nationalizing industries, seizing production, halting trade, all under various War Powers Acts, which the President alone can invoke. Of course after the fact Congress has some oversight, but not much.

Last Trump term he declared all sorts of things were national security issues then applied tariffs, despite those powers never being used as ham handedly as he did. I suspect we’ll see more of these uses soon.