Seems that the concept that sadomasochism being a sick psychological behavior was formally pushed into the belief systems of the masses by one or two scientists/psychologists. Later the gay community trashed that concept successfully. Today we have such films exposing it as merely an alternate lifestyle choice as shown in 50 Shades of Grey and plenty of gay leather websites and clubs that participate in it.
We also had one or two scientists who sold the masses on the concept that there is a sadistic virus that tortures and kills. The gay community has masochistically accepted this torture though it doesn’t have to be that way.
As with Freuid, Gallo too was wrong in his findings.