My 2 points would be the Army gets the pistol they want, and they be built in the USA with American labor, and I suspect it will be. Seems to me, Sig has much of their manufacturing in the USA.
I guess I don't understand why there would be fanboys that care what brand/model pistol they use, sounds like ego to me. They wanted a new handgun, set the criteria and picked a model. I can tell you the fanboys are definitely out there though. I bought a new Beretta M9A3, and people went out of their way to tell me that model was rejected by the Army, I guess assuming my like of Beretta pistols is based on it being adopted as the M9?
I don't really want an old worn Beretta, but hopefully the M9s won't just be scrapped as they are replaced, but it would not surprise if they are, probably some executive order from a former elected jerk won't allow them to be sold.