I hadn't known JN-T was gay. Interesting that both the last producer of the original series and the first producer of the new one were gay. It makes me wonder if other producers were.
IFAIC, Nathan-Turner's eight predecessors were all straight.
Certainly, Peter Bryant, Barry Letts, Philip Hinchcliffe and Graham Williams were all married with young children, while Derrick Sherwin was married to the actress who played Lady Jennifer in The War Games. Not proof that they didn't swing the other way on the quiet, of course, but I'll take it at face value.
ISTR mention of a widow and children in Innes Lloyd's obits, but that's 20 years back so can't be certain. If John Wiles had been gay, I'd suspect someone might have mentioned it as a possible explanation for the well-documented bad relationship between him and the somewhat intolerant Hartnell. As for Verity Lambert, she was married briefly in the 70s: could be any number of reasons why it didn't last, but I suspect that we probably don't need to look for anything more than her being a strong-willed, acid-tongued career obsessive...