I have noticed that too. Extramarital sex has been de rigueur for a long time, but the adorable gay people are a new development. One of the reasons I like the C. J. Box books is that the hero is a faithfully married man. Swoon.
When the first novel appears in which the gay person is the murderer, then we will know they have arrived.
The other novels I have come across all included males, and several times they provide food for the protagonist. Harlan Coben's mystery novel has been the most extensive, some saying it sounds almost like recruiting. That novel was the first one I've read by him, so I don't know if he includes the "adorable gay" in all of them or if he just "came out."