It sounds like something that would be very easy to fix if the government mandated that insurance companies have a responsibility to keep their provider directories up-to-date. Software should be able to very easily identify providers that have not accepted any claims in a given time period, so that they can be flagged for removal.
This has been the case for a long time. If you don't believe me, why not break out the old phonograph and spin up the classic 1961 album "Ronald Reagan Speaks Out Against Socialized Medicine", in which Ronald Reagan (the actor?) warned us that Medicare is just a "foot in the door" toward becoming an authoritarian dystopia where the government tells everyone which town they're allowed to live in? Just ignore the fact that it was produced as part of a stealth campaign by the AMA [1].
