There is plenty of evidence that regulation is required. Even before yesterday there is a laundry list of violations. Verizon has even explicitly stated in court that the neutrality rules are what is preventing their plans to block websites that don't pay their tolls.
Yes there was.
They are working on the rule of thumb that we shouldn't have a regulation unless there is significant evidence that it is needed.
And the truth is there is not a lot of evidence it is required.