1. I don't have enough inside in that matter, but I do know Amy Henning was really good. But I am sure game companies are also forced to hire diversed people for the best paying function's and that they are more likely to get promoted even though it may not always be the best decision. The locational manager of my school has even admitted that she got multiple functions for just being the woman and encouraged her female students to do the same.
2. Half of the people on this planet are women, so including them literally doesn't do anything for inclusion. Hell I would even say games without woman characters feel weird. For homosexuals you kind of have a point. Being gay isn't all that common so why should it be in games. If you can be gay in your typical RPG fine. But I don't see a protagonist of a SP adventure game being gay as a pro unless it actually affects the story.
3. I think we can all agree on that one.
The last of us was a good game which had a non stereotypical black guy and Ellie was gay and that actually added to the story. So developers can add diversity/sexuality in a game while it doesn't seemed forced. But I guess they are afraid you wouldn't notice them if you did. So forcing is the better the option I guess or just lazy writing.
Please excuse my (probally) poor grammar