Article I, Section 8 of the US Constitution assigns responsibility for regulating the value of US money to Congress. IF Congress disagrees with the action of the Treasury Secretary, it (Congress) has plenary power to do something about it.
Then hope the conservatives in this Congress will do as their electorate wishes them to do. We must let them know!
As you know Congress did just that as one of its first acts when it set up the Treasury Department. Of course, at that time it was run by one of the world’s great geniuses.