It was a bad transition, but there was no regulatory reason to block it. If Verizon had been trying to sell to Time Warner or Comcast, which would have reduced ISP choice for many people to one provider, then there is a regulatory role.
You call a "bad transition," but is that just the PR line or has the anti-consumer behavior actually stopped?
>there was no regulatory reason to block it
That's a problem, no? If protecting consumers from harm isn't a reason that empowers them to block it, the commission is broken.
"The CPUC serves the public interest by protecting consumers and ensuring the provision of safe, reliable utility service and infrastructure at just and reasonable rates, with a commitment to environmental enhancement and a healthy California economy." http://www.cpuc.ca.gov/
CPUC can't predict how well a transition like this will happen and they can't ban all telecom sales because service might be temporarily disrupted. You would be worse off long term stuck with Verizon if they were actively trying to get out of the market. They had already killed all new investment in FIOS years ago.
There's that "transition" line again. Still nothing to back up the idea that it's a temporary situation rather than the "new normal." Or more accurately the "new low."
>they can't ban all telecom sales because service might be temporarily disrupted
All? Of course not. But banning ones that create monopolistic / oligopolistic situations in certain markets (the predictable effects of which are higher prices and worse service, including more frequent interruptions of service) is warranted.
In a hypothetical universe where all possible mergers would result in monopolies / oligopolies (and are therefore blocked), that's a feature not a bug.
In this case they could have based on prior frontier acquisitions from Verizon. When they first announced it I googled them (because I thought they were an airline and that made no sense) and the first things that came up were about how bad the transition was elsewhere.