We have had homophobic attitudes in Call the Midwife, I remember when Richard Hesmond-something played a young married man whose wife had a baby was caught making pass at an undercover policeman in a public loo. The world and his wife were down on him in Poplar, it was horrible. Dr Turner had to prescribe hormone treatment for him and monitor him regularly, in order to keep him out of gaol. He wasn't happy about it but he had to. The poor guy even tried to commit suicide.
There have been a couple of others too, I remember one guy going to an awful clinic for aversion therapy but was rescued by Dr Turner and Phyllis.
I don't think it is unreasonable for people like the Turners, who see so much of other people's lives, to have a sympathetic attitude. There have always been some who come to realise that people are born that way. It just wasn't mainstream.
The other thing is people change their minds and modify their ideas with age and experience. I am 72 and know that is true, I've seen it. When I was a kid I remember being told that homosexuality was a mental illness!