So exactly how was this different from the US at the time? Granted, I was not around for most of the '50s, and too young to pay attention for the rest, but by the '60s it was fairly open, at least among younger people in the places I lived. (Of course the US was and is considerably more diverse than Britain.)
We might also note that (as of this election) gay marriage is legal in a fifth of US states, but not in Britain.
I think the difference I saw, James, was the fact that in the US, people didn't speak of it much in the open, as much as in the UK. This was in the early '60's, when I first came to the US. Many who were homosexuals here, never admitted it. I think only in recent years, have most 'come out'.
I also think that some, think this is something modern. It has been well known and documented, for many hundreds of years and in many countries. It was so widespread in the 1500's and before in the UK, that (I think) it was King Henry Vlll who outlawed the practice. He being head of the new Church of England. Not that he had room to talk really, of anything concerning morals!
There are I'm sure, still wildly funny old laws on the books, in many countries. I remember as a four or five year old, I lived in a small village in Norfolk. On the village green was a grand old oak tree. Probably several hundred years old. From a branch, hung a chain attached to a metal thing which would be put over the head of a criminal and locked, so all the locals could see who had done what. I was told women were often placed in this head thing, because they had been found guilty of 'scolding'. This either their husbands, children or somebody else. I believe this particular law was only brought to an end, in the 1960's.
I also remember when I was about 5 years old, going to the local little shop to purchase cigarettes and a box of matches, for my doctor's wife. The shopkeeper could sell me the cigarettes, but not matches. He said it was illegal to sell matches on a Sunday. I remember that, to this day. It was a little shop, half way down Grapes Hill, in Norwich. Funny stuff. I wonder if it is still illegal to sell matches on a Sunday, in England.