It's simple supply and demand. If the average dev can do that, then that's what will be demanded. If the average dev can't do that, then there's no use demand

It's simple supply and demand. If the average dev can do that, then that's what will be demanded. If the average dev can't do that, then there's no use demanding it since there's no one to fill that opening (at that price point). The software dev supply market is absolutely saturated.