When a Browning Hi-Power is involved in a shooting that results in a court case...You can be sure that the opposing lawyer will investigate whether the Hi-Power magazine disconnect safety has been removed or not.
If it has...the opposing lawyer can build a case...that the user of said pistol was irresponsible with gun safety at the time of the incident.
No, this is an old wives' tale that predates the internet itself. This superstition, along with "don't use reloads for defensive purposes" just won't die...