Milton Friedman made a good career proving you wrong with his helicopter money. Dumping cash in human hands has real effects beyond increasing the price of everything.
(I agree that the parent comment is unconvincing.)
(I agree that the parent comment is unconvincing.)
They are independent entities as measured state of an economy at single points in time. Money supply doesn't tell you what GDP is, or vice versa. Normalizing GDB for inflation is about removing even that connection.
But as far as the dynamics of an economy everything is related to everything. Changes happening to one spill into effects on the other, although as we both know, often not in a simple way.