Well, then can I ask who you think is going to protest? Butch liberals?
I'm just not sure I get what/who you are worried about. Not trying to mean, Mods. I just am not clear on this.
Yes I get in the early 2000s Bryan Singer didn't add any LGBT to his X-Men, he's not really one to extend the door to others as it is but back then was even a more conservative time. TV in general skews more progressive since ad revenue and budget can be adjusted over the run, it's not reliant on that one opening weekend spectacle. They can introduce concepts over time and in different ways. ABC's "Revenge" had a male character who was shown with women, then revealed to be bi after waking up with a guy.
I doubt they'd have Constantine with a guy right off the bat, it wouldn't be true to his character anyway. He seems predominantly with women but not always.
We can make a guess at what type of an audience is attracted to shows like these, generally less traditional than even mutants and superheroes get. Saul has a point in Torchwood, I mean the character here is even British. Everyone hopes British guys are Bi, look at Sherlock fans.