The argument being made by some that the current President cannot change what a previous President did is an absurdity. Congress is not bound by what previous congresses have done. The Supreme Court is not bound by what previous Supreme Courts have ruled.
Sovereign Authority: Each Congress is considered a separate and distinct legislative body. This means that the decisions, rules, and policies established by one Congress do not obligate future Congresses.
A Presidential administration is a sovereign authority, not bound by the acts or orders of previous administrations. Any actions of a President that have not been legislated into law by Congress is not binding upon a new administration.
The President is obligated to fulfill Congressional mandates as he sees most fit. A current President is not obligated to maintain how previous Presidents thought fit to do so.
The Supreme Court can rule on the constitutionality of a law passed by Congress but it is up to the Executive to determine how to apply and execute those laws. The Supreme Court has no authority to rule over or otherwise interfere with a President’s Constitutional authority over the Executive branch. It is within the authority of Congress to curtail or control how Presidents execute their authority.
We do not have three equal branches of government. We have three branches, one of which is first among the three. Congress has the ultimate authority. It can remove Presidents and Judges; neither of those two has such power over Congress. Congress has that authority over itself. The people have the final authority over the makeup of Congress.