Do they really think they're going to hold more sway with Comcast or Cox?
The gubmints still haven't figured out that if they don't enforce the agreements that they struck with companies as part of their support of assembling megacorporations, the desired results will never come. What you permit, you promote and you can't roll it back.
Well, technically, NY could try to force the dissolution of the merged company, as they agreed to the terms of the merger, and those terms have not been met. AFAIK, this may never have been tried in court, and I doubt NY wants to pay for a lengthy legal fight over telecommunications. They can instead revoke their license and force Spectrum to either spin off or sell the business in NY, or, more likely, threaten to do so to get Spectrum to do what they promised to do in the first place.