Yah, if you look at the screenshot of the group, there are 6 males with weapons (Varric, Iron Bull, Solas, Blonde dw rogue dude, bearded warden dude, and the mustached mage dude), three females with weapons (Cass, Viv, Sera.) There is one male with no weapon (Cullen) and two females with no weapon (Leliana, and scribe girl)...these three as assumed to be advisors/agents.
Well, that does suck and I don't really get why they randomly went 6/3 on the companions. As far as the advertising goes I do still see the logic in it though, even if it may not be ideal for people.
The trouble is, I don't see how having a female Inquisitor in a trailer which more prominently included a male Inquisitor would effect sales badly?
You can't really say 100% for certain how a single scene with a female inquisitor would affect sales or if it even would at all, although the general accepted guideline is that it's more effective to throw everything behind a single recognizable face or mascot, and gaming is still viewed as being dominated by male gamers. Unfortunate and not entirely true anymore, but that's how it is.
To be honest, personally I suspect only having a single scene or so would just cause confusion. A number of people would probably think that the female inquisitor was somebody else, seeing as how the male inquisitor has already become the "face" of DA:I.
and of course people would complain that the trailer was still mostly about the male inquisitor and the female one barely got any screen time, but this is the internet and if you don't do things because people might complain you wont get anything done(and then people will still complain that you didn't get anything done).