They have the monopoly on the infrastructure they will drop prices below wholesale and with their deep pockets and USF funds wait out the competition. Once they have run most out of business they will start slowly easing prices up until they are higher than what they are now.
All you have to do is look at how they handled the USF fee to see why they need to be regulated. In the Greenville/Spartanburg area we have no competition. Charter cable sucks so scratch VOIP. Sure we have cell phones but rates are high, you have to commit no matter how bad service is so BellSouth is still the only phone service many have here.