Even though Sidney was openly gay in the television movie that the show was based on, the producers toned down that aspect of his personality when the show premiered due to the fact that they were afraid that they would not get any sponsors for a show featuring an openly gay character.
Although this was the first TV show about a gay character, Tony Randall, the actor who played the lead, was not gay.
Tony was married to his first wife (Florence, his high school sweetheart) for over 50 years, until her death, and then sired two children with his second wife (Heather) when he was in his late 70s.