I know 2 people who own a bunch. both collect firearms. neither have killed anyone.
this ain't the number of guns. since he don't have 47 arms. It's a fact i bet the guy has something loose in his head.
having 47 is no more dangerous then having 2.
I know a collector that has close to 100 guns, most of which are antiques guns (1898 or prior). These guns are locked in a walk in safe (10' W x 12' L) in his house. This safe is like Ft Knox as it's encased in re-enforced (rebar) concrete.