You don't have to go to the east coast to have trouble finding them. In St Louis they have a whole 4 flights, and 3 go to the west coast. So yes, absolutely regional. And that's the western side of the midwest. In comparison, Southwest has 55 direct destinations from the same airport. This isn't cherry picking: You have as sparse a route map from Dallas, yet another non trivial city. From there, Southwest has 70+ direct flights.

So yes, still a regional airline if your home base isn't exactly on the west coast.