Wasn't the thinking at the time you could be a security risk if discovered by the other side and blackmailed
The Alan Turing case is indicative of thinking at the time. Turing was prosecuted in 1952 for homosexual acts; the Labouchere Amendment of 1885 had mandated that "gross indecency" was a criminal offence in the UK. He accepted chemical castration treatment, with Diethylstilbestrol, as an alternative to prison. In 2009, following an Internet campaign, British Prime Minister Gordon Brown made an official public apology on behalf of the British government for "the appalling way he was treated". Queen Elizabeth II granted Turing a posthumous pardon in 2013. The Alan Turing law is now an informal term for a 2017 law in the United Kingdom that retroactively pardoned men cautioned or convicted under historical legislation that outlawed homosexual acts.
https://en.wikipedia.org/wiki/Alan_Turing