[T]he secret origin of the secret origin of the new Batwoman, a one-time recipient of a PR bonanza, who's now so secret you never hear about her.I agree with Mr. Spurgeon about media corporations' use of the "Look Here! She's Queer! Don't Get Too Used To It!" stunt.
Surfing the PR of an event with positive ramifications for gay people and then burying that event/character/plotline later on, whether intentionally or unintentionally, is such a part of the American corporate entertainment landscape it would probably have a name except nothing sticks around long enough to give it one.
But you also have to remember that the two major super-hero comics companies, Marvel and DC, have had absolutely no success with long-term development of any new characters for the last 30 years. The last super-heroes to be added to the pantheon of heroes licensed to movies/tv/underwear/etc. were the new X-Men from 1975. And even they were essentially the retooling of the 1963 Jack Kirby/Stan Lee creation.
For three decades the Big Two have been in the character exploitation business not the character development business. There's no reason to believe that DC treated the Batwoman character poorly just because she was gay. She was treated poorly because that is how DC and Marvel treat all of their characters.