N380UA:
The whole point is that you would have spent your US$2.5 bn on an established long-haul network with a hub (in the case of our example BA that would be LHR) at which slots come at a premium. From a Swiss point of view, you’d also have a well established commuter/regional carrier in the form of LX which, if necessary, could fly the odd long-haul route that makes economic sense out of ZRH/GVA or BSL (maybe NYC, HKG).
Europe is overcatered to in terms of air traffic. The place is full of micro and mini hubs, all within 30 to 90 minutes of each other. That would not work in the US, and it is becoming increasingly visible that it doesn’t work in Europe either.