The statistic on Garrus wasn't even taken on a game where Kaidan was a choice, though. Miranda got something like 40% of the LI choices in the same game, where as Garrus was only something like 5%, if I remember right. I don't think he was really the main romance "by far". I'm pretty sure it was like a 2% difference between him and Jacob.
No, he wasn't the main romance by far in the game, that would be almost impossible given that < 20% of ME players play FemShep, but given the option of him, Thane, or Jacob, he was the most romanced according to a really unscientific poll that we shouldn't give any weight, but since the person who mentioned it linked it, I thought I'd say something about it.
However, even outside of that poll, I'd say that Garrus and Kaidan are competitive as LI's as far as popularity goes. It's hard to compare them directly considering the fact that ME3 is the only game wherein you can romance both of them, and one is unavailable for new romances while the other can possibly be dead. But regardless of even that, Garrus is an extremely popular character and love interest for people who play FemShep, despite the fact that he looks like a giant metallic cricket, so I can't see them nixing Solas, Varric, or Iron Bull simply because of that.