Monopoly

In a 6:3 decision the supreme Court overturned a lower court decision to give ISPs access to cable. This will put many ISPs out of business. That has already happened in many places. If the phone companies say, ok if cable companies don't have to share their connections, why should we? If the courts again agree, then the phone companies will have monopoly control of the Internet. What are they thinking, or is this political payola? After all how can we accuse the Supreme Court of an illegal collusion to grant an illegal monopoly? Another crime in the trillions, what is it that I don't understand?