What if ISPs started blocking Internet service to computers running out of date OSes?
What if the greediest and laziest of American companies decided to turn down money from some of their customers? Are you really asking that question?
Short of a federal mandate, there is no way that's happening.
And the telecoms sued the FCC over being regulated as common carriers, which they fairly obviously are.
You think this could happen without a protracted court battle? No chance in Hell.
Let's not forget that a sizable group of Republicans tried to revoke the FCC's authority to designate ISPs as common carriers when Wheeler announced the net neutrality rules. So even the hope that there will be a mandate to fight over in court is laughably improbable.
It would take a minor miracle for anything useful to be done regarding residential network security. Maybe if the entire US gets turned into a botnet and the internet is down nationwide for days or weeks---but even then I doubt it.