The whole "I went through this, so deal with it" and "You should have to go through what we had to" attitude however, I can see why people are getting annoyed about. I understand why people feel this way, but it doesn't excuse the way people are coming across at times. It makes those posters look petty and downright spiteful.
You will never convince me that straight men are being oppresses, excluded, or are being discriminated against when it comes to video games, so arguments based around straight men seeing themselves as oppressed, excluded, or discriminated against are not meaningful to me.
As I've said, the situation they're complaining about is not one I'd consider unfair when applied to myself. If BioWare had said 'We're making two female LI options bisexual and one straight,' I'd have been okay with this.
Moreover, I expect that straight men will end up still getting more options than queer women. I find the wringing of hands on the subject bizarre.