If they are focusing entirely on the depth of mechanics, mod support being integral, or highly iterative design over a long period, or a focus on mouse and keyboard input, then is absolutely could miss out on consoles. It would be the same story as countless games that are only on PC. First and foremost to come to mind is Firaxis' own Civ V, selling 7.4 million and only on PC. There could be something like an Xcom version of Civ Rev that is more tailored to consoles, who knows. Regardless they are explaining specifically the decision to be PC only, this week via IGN and I'd guess also via tomorrow's livestream