Because the supernatural is by definition outside of reality. The null hypothesis can never be proved. It is solipsism, but a cherished, closely held and defended fallacy. God does not need to be defined in terms of magic. That which is real and has power need not be ephemeral. The trouble is that God has become narrowly defined as the God of the gaps, or worse just the God of desert tribes. Choose an understanding outside of that and you are labelled a heretic, or condemned as possessed.
The labeling and condemnation are specious. I fully defend the right of anyone to believe as they choose. I do part company when it is attempted to legislate those beliefs to oppress other humans, or inculcate sloppy thinking in children. If you want citations, I'll be glad to oblige, but women's health is an easy one. Religious education another.
Peace,
Julie