I think some people still don't realize quite how expensive it is to truly build out a national Telecom network. I remember when Clearwire raised ~$7 billion [1] and still wasn't in many markets and rural areas, ultimately selling to Sprint for pennies on the dollar. The infrastructure costs are staggering, and even a rich company like Google can't just dip their toes in hoping to succeed.
Yes, I agree this is the key here. Google realized FTTH is too expensive in most places, and still are looking at wireless IIUC. Except for new buildings in dense areas or similar, it's likely that bringing fiber close and going over the remaining distance with either 3.5 GHz radio or millimeter waves (former better for range, later for available BW) makes more sense. We'll see soon how well it works in practice, 5G NR deployments will start with fixed wireless like this.
[1] https://www.crunchbase.com/organization/clearwire#section-fu...