Every time the gender preference issue came up in DA2, Bioware (and DG's) position was that people should have access to all LIs. That was a design choice they defended. While obviously that doesn't mean DA:I will be similar, I think it would be a pretty radical departure from them to do it. So while it's true that Bioware hasn't come out and said anything, I think excepting gender preferences to be fixed is a bit like expecting dual wielding warriors to come back: pretty unlikely.
While that may be true, it is also true that we have not been given confirmation about it one way or the other and we frequently have devs telling us not to assume anything. So with that in mind asking for clarification before getting your hopes up seems like the best thing to do. Nobody has demanded it, they have just said they felt disappointed. They just want to be allowed to be as excited about the announcement as the other fans, or they want to know that there is no point in getting excited, so they can turn their attention elsewhere.
Yes, People who don't have a Problem with playing straight male characters will be able to romance Cassandra. Now they know, that's good News! You don't know if you'll be able to romance Cassandra, I don't know if I will be able to romance Iron Bull, other people don't know if they'll be able to romance Varric. That's the way it is, no Unfairness that I could see.Also, if you're as unflexibile in your roleplaying as you say you are (that's fine of course, no offense) you'll probably have to deal with not seeing several things that you will only see when taking a different approach. That's the nature of roleplaying games and that's the way I like these games to be. The devs said they would either represent every sexuality equally or choose playersexuality, so if we get 2/2/2 you still have plenty of options. If Cassandra is none of the bi or gay options that's sad for you, I can understand that, but in some way it's part of the roleplaying experience. Cassandra happens to be straight in this case and if that's the way the writers intended her to be, None of us has the right to complain imo.
None of us know if we can romance Bull. None of us know if we can romance Varric. Straight people know they can romance Cullen/Cassandra as their own gender. Gay people do not. That seems unfair to me.
I don't actually think it's the romances themselves that upset Gaider, but the way people treat them as a given. And the outrage it often creates, no matter what they try.
He's included romance in all his Dragon Age books after all, it can't be that he doesn't like romance as such.
But I can understand getting tired of the fans excessive demands towards it. Usually a writer just wants to make good stuff and not have to please everyone.
The OP was asking for clarification, not making demands. I don't see what is wrong with that.