Aiden is what I would call a safe choice. Really no one has made a compelling arguement why it is in the publishers interests to deviate from that.It's clear that people have personal reasons. But I just don't see what is in it for the publisher.
Aiden isn't an asset. Being the safe choice isn't always good thing. A truly memorable protagonist makes a game better.
Additionally, if the compelling argument you are looking for is based on pre-existing monetary information, it doesn't exist. Because gaming hasn't really attempted it yet. The point of all of this, is that the straight white male audience isn't the majority of gamers, and greater inclusiveness is needed in every sense. We need more LGBT protagonists, we need more people of color as protagonists, we need more women. Hell, we need more LGBT women of color. We need intersectionality. The demographics are changing and everyone deserves to be represented. Believing games with new and different protagonists won't sell if given the same exact resources, time, and talent, seems to be arguing that the gaming audience is too homophobic, racist, and sexist to accept anything other then a straight/white/male. I refuse to believe I've devoted my time, energy, money, and enthusiasm to a medium run and consumed by people who truly think that way. At the very least, it is in the publishers best interests not to let their brand become antiquated or associated with sentiments of anti-inclusivity. And to do that, all they have to do is continue making badass games, only, add some diversity to their leading roles.