Does the cost in maintaining/paying for hub airports factor into why airlines are regional? For example southwest has service over most of the US because they u

Does the cost in maintaining/paying for hub airports factor into why airlines are regional? For example southwest has service over most of the US because they use the older/cheaper airports vs United has hubs that don't heavily overlap with American. I don't see the parallel with ride sharing here. I think Uber/Lyft can take over the whole US since they don't need to maintain much supporting infrastructure. Plus they can get economy of scale in marketing.