The American Psychiatric Association opened that Pandora’s Box when it declared homosexuality was not a mental illness.
The reason they did this was that the early gaystapo harangued, harassed and intimidated dissenting opinion.
It actually never declared it was not a mental illness but it did vote to leave it out of the DSM for political reasons. No research ever done has shown homosexuality to be anything other than a mental disorder. Prior to this act or since.