Chaosmancer
Legend
I really have to disagree with your assertion.
I suspect that what happens at virtually every table is some brief "As you walk down the street you see children weeping into their parents arms, couples comfort each other in the shadows..." etc. I sincerely doubt anyone bothers describing the exact sexual orientation of every couple they walk past, because honestly it is completely irrelevant to the game and to the narrative. The only purpose of describing it in such detail is to pursue a political agenda, because I suspect almost no-one is playing a game where they're handling a disaster scenario and is focused on determining the sexual orientation of the NPC's.
If we were talking a murder mystery, or a missing person, then sure the sexual orientation might be relevant insofar as the PCs need to know who they're looking for, but beyond that it's almost always going to be irrelevant.
I've been trying to avoid jumping into this topic since its inception, as I really don't have any problem with any kind of relationships, but we're crossing the line between reflecting the realistic relationships when we have to define such relationships in situations where they aren't relevant to the game or narrative, at that point we're no longer pursuing the topic of being X-Phobic and we're starting to pursue the topic of political statements.
This is a point I'll jump into, why the heck not.
First off, painting the tragic scenes with loved ones can be good storytelling. I still remember seeing a commercial for the "new" (couple years ago) Titanic movie and there was a scene with an elderly couple, lying in their bed on the ship, holding each other in the dark, as the water rose up around them. It was... beautiful and tragic. That connection of seeing people losing hope, of despairing is huge.
Now, sure, if you're quick pacing through a faceless city as it is being ravaged by a Dragon and skimping on the details, you may not find the need to call out specifics. But, assuming a homebrew, what if this is a city your players have spent a significant amount of time in? What if you built these relationships, made your players see these fictional constructs as people? Then it isn't "couples weeping over their loved ones" it can be "Brad cradling George's limp body". The impact will be huge.
And trust me, it does not need to be obvious. I remember rereading the Magic Circle series by Tamora Peirce with my little sister. I'd read the series in Middle School and enjoyed it and wanted to reread it. One of the major characters comes close to death in the fourth book, and after they are saved another major character runs up and hugs them. First time I read it, didn't register. Second time? I realized quite abruptly that these characters were in a same sex relationship. I couldn't believe I had missed it, and even went to the official wiki to check. It was so subtly woven into the story, because it wasn't the focus, but it was there and it helped to add something to that scene to make that realization.
My point is, if you ant to gloss over the details you can, but if you really want your players to go crazy, build these things up. And if you're ding that, no reason not to be more diverse in your representation.
Also, to an earlier point about a lesbian necromancer and assassin, for some reason my first thought was that instead of being an assassin she should be a barmaid or gardener. Someone completely ordinary and starkly not what you would expect.