"You don't care about good stories, you only care about representation."
"Your unwillingness to accept LGBTQ characters reveals your latent homophobia."
"You're not representing LGBTQ players effectively if you're just tacking on the tag at the last minute before your story goes to print."
(These aren't actual quotes, just a characterization of how these conversations typically go.)
It's an important topic, and both sides are important ends of the spectrum. On one side, as a writer you want to make sure that your story is diverse enough to appeal to a wider audience. If your game's world is filled with white people, any black player entering that world will feel isolated.
On the other side of the fence, as a writer you want to maintain your artistic integrity, and develop your world in a way that's believable. So you don't want to just throw in a gay character "because diversity". If you've never met a transgender person, you don't want to start writing a transgender character that may offend that segment of your audience.
Both sides are right. You don't want to offend the audience you're trying to represent, and you also don't want to exclude that audience entirely.
The question we should be asking ourselves as writers isn't "Should I include diverse groups in my writing?" but rather "How can I make my writing represent a more diverse audience and still tell a good story?" When we start thinking of the how, suddenly the "problem" is revealed to be a challenge instead.
Those of us participating in this debate, we all agree that there needs to be more diversity in our stories, in our characters, in our worlds. More diversity leads to better and more diverse stories. So let's stop arguing about whether or not we should or can do it--let's stop focusing so much of our attention on the Bechdel Test and whether or not that crap film we saw passes or fails--and start talking about how we can do it well in our own writing.
I realize I'm providing no answers here. That's the job of the individual writer, and everyone's creative process is different. But we've been wasting a lot of energy trying to convince people that this thing needs to be done. That energy would be better spent actually doing it.