FDR either blatatantly ignored the federal governments constitutionally limited powers, or did not understand those limited powers.
Regarding domestic policy, are you aware that one of the very few powers that the Founding States had actually delegated to the feds, expressly via the Constitution, to regulate an aspect of INTRAstate commerce is to decide policy for the US Mail Service (1.8.7)?
In other words, you can bet that most other federal government services, Social Security, welfare, etc., are unconstitutional and end up winning most of your bets.
I won’t disagree too much but remember the times, The Depression. There were several Supreme Court decisions that invalidated New Deal Legislation but there were also some that went way over the line and invalidated aspects of the Constitution.
We are past the point where Black Letter law and strict interpretation of the Constitution will be done.
As Garet P. Garret, Saturday Evening Post Editor on the 1930’s and 1940’s, opined in 1938, The Revolution Happened without a shot in November 1932.
There is no going back at this point. The people will not let it happen. So there you are.