It simply opens the door to federal control for due process, before someone's life can be terminated there must a finding of fact that they are dying or have no chance of recovery and that their wish was to have life support terminated. Both conditions are controversial in this case and the legal proceedings to make those determinations have been woefully inadequate.
It opens the door to EVERY SINGLE person on a feeding tube in this country this very minute to go through this same process; the Congress will now decide who lives and dies.
Whether or not we agree with the decision her husband made, she's had more "due process" than any living party to an ongoing case.