Good for him, my father did it the hard way by refusing to eat ot drink anything until he died after 2 weeks.
His knees had gone bad and he wanted out and who in the family has any right to stop him, he was 92.
Anyone who cares has a right to object. Free speech is given by God. Others might not like to hear it, but objections at such a time should be voiced.
My father did the same, it took that tough old Coot the full fourteen days to starve I was privileged to sit and be with him that last night.