I would love to read your statistics on that.
But that takes us back to the chicken and egg situation. Games that are targeted at the male straight gamer will most likely have the male straight gamer as their key fanbase. As David Gaider has put it so eloquently: "Game companies should stop treating 47% of players as an added bonus".
I kind of dig the man.
ME 1 and 2 had male/female and female/female relationship option. M3 had that and male/male relationship option.
So, ME 1 and 2 at the least targeted every demographic for romances except gay males (untill ME3), and the player base was still 82% picking male shepard.
Now, if they can determine how many people selected male shepard over a female Shepard, one would think they could find out the romance options selected just as easily, and if male/male option was high on the romance option, don't you think they'd blink, go OMG, and then start cramming more of it into the game, purely for the sake of more money (which many agree the point of the cartel market is them wanting more money).