That is not a solution, municipal fiber is the fix for the last mile. Comcast could use is as well as anybody else that cares to, either colocating gear in the muni co or just running a fiber trunk. CWDM is cheap, simple, and requires no active (powered) components at the muni level. Macsec and similar can keep the muni from tapping into the traffic. The only thing they need to do over the fiber is keep track of what colors are in use for a given run so they can assign unused ones.
From a homeowner perspective one fiber gets them everything.
Business get the same plus intown point to points for less than the cost of a couple phone lines.
The muni gets a network to connect itself with (I know many that pay absurd amounts for DS3 etc). If the muni chooses to put a L2 network in they could resell that to small providers etc etc, while giving lifeline internet access and a universal service (think the town services, schools, library's state and federal level gov probably expand it via a review process to medical facilities serving the area etc etc. Muni's are also in it for the long haul so the cost of buried fiber can be justified with it's less frequent outage and more aesthetically pleasing nature.
Other cable/internet/phone providers could come in and compete as the build out costs to the muni CO are pretty trivial.
As this grows providers will bridge muni co to muni co, the muni's may well cross connect to the towns bordering them.