Well you can hold them up to an agreement they made, if they made it, which I'm not privy to.You can't force a business into a money losing deal forever
Maybe they got to use eminent domain if they agreed to wire every house. Maybe they got the free bunkers I previously alluded to. The way out would be if they bought back what was given to them, or, if, as you say, they substitute an appropriate, reliable technology like external cellular/ satellite doohickeys.
The issue I have, is we as a people have lost the will to regulate cable/ internet companies as a utility. They still consider themselves a luxury convenience. When phone and power companies hit it big 100 years ago we demanded more of them, and that's an us problem-- ultimately we gave them both the power they're wielding.