1 I do not know a very good example and frankly I do not care. Ellie and Bill where gay in the last of us and that is a masterpiece do with that what you want.
2. I truely don't and its a given that in most RPG's nowadays which offer relationships you can be a black bisexual woman which kills trolls I think the whole situation is a bit overblown. Writers should have total freedom to make the character hé or she wants and should't be constrained by rules so that LGBQT are minorities are represented more in games. So I agree with Ka-Pi
3. Probably not since everyone whines so much about them, frankly I care little about it, if the game and the writing remain good sure, if devs are trying to score SJ points and ho out of their way to make a gay character and explicitly let you know that it usually goes at the cost of good writing and immersion, so in that regard I am not a fan. Although I must say except for Persona 5 I rarely see the latter form.
Please excuse my (probally) poor grammar