Two days before the fall of the Berlin Wall another wall of sorts fell on network TV when the critically acclaimed ABC drama thirtysomething showed a gay male couple in bed having a post-coital chat. The episode was called "Strangers" and it never aired again - largely due to advertiser resistance. However, it's available on DVD (season 3). By contrast, a scene like this would be considered chaste by the standards of TV in the 21st century. (Case in point, the premiere episode of ABC's How to Get Away With Murder in September 2014 showed a scene in which one gay character rims another - to no uproar whatsoever.)
ABC had a reputation for pushing the envelope vis a vis portrayals of gay issues. It aired the TV movie That Certain Summer in 1972 about a divorced father disclosing his homosexuality to his teen son. Then in 1974 the popular medical drama Marcus Welby MD aired an episode, "The Outrage" , about a high school teacher who raped a male student. Billy Crystal (left) portrayed an openly gay character in the late '70s sitcom Soap. Another TV movie, Consenting Adult, aired in 1985 and told the story of a young man coming out to his parents (played by an overwrought Marlo Thomas and a disapproving Martin Sheen). Finally, in the 1990's the sitcom Roseanne had two regular gay/lesbian characters - played by Martin Mull and Sandra Bernhard, respectively.