In many areas exclusive municipal cable contracts exist even today.
Look how hard Verizon had to fight just to get apartment building not to have exclusive agreements(that has been within a year or so).
Those exclusive municipal CATV franchise agreements that still exist today are the ones that have not yet expired. But it is no longer legal for municipal CATV franchise agreements to be exclusive, and so it is pointless to suggest such a reform.
Apartment building exclusive contracts are a different thing than exclusive municipal contracts.