When Google Fiber was originally planned, Google was free to plan its business model as it pleased. The future value of the broadband channel was already deemed minimal. The real value was in the services that could be offered over it. Now that the FCC is involved, the government can and will ensure that there will be NO massive profits to be made in laying all that fiber. So why do it?
Net Neutrality (as it is inevitably practiced) means that the broadband of 2015 will be the broadband of 2035. What we are seeing broadband today is what we saw in the Telephony industry in 1935. Consolidation of the little companies into massive monopolies that can use the economy of scale to be efficient in a market with low profits. No major innovations for 40 years.