To give Congress a chance to do it's dadburn job. Not that difficult actually. They are supposed to make the laws, the President simply enforces them.
I don't know what so hard about understanding this but of course in the world of Trump Derangement Syndrome sufferers the first response is always to assume the worst.
Unconstitutional law should be made constitutional by act of Congress or it should be deleted. They have the time but where's the will?
Like so many things that need to be done but stalled by petty party politics.