Law is a human construct, it is essentially a consensus structure. You can hold up a piece of paper that says "I can do what I want" and maybe it's even legitimate, but you still need to convince other people of that and our legal structure/precedent puts more emphasis on process than being efficient or fast.
In effect, the law has stopped trump from doing just about everything he wants to sans a few items. Every time he tries to do something he has to fight a bunch of people and that takes up some of his finite time and resources.
Just because he has friends in all the high places doesn't mean everyone else will just jump into line and do exactly what he wants, the more people obstruct the less damage he can do.
In his circles apparently HGH is viewed, erroneously, as a life extension drug. It wouldn't surprise me for an instant if he was mainlining it out of a fear of dying like a common peasant.