It is impractical and irrational to wire up a home to multiple ISPs with their own fiber channels. Each channel could cost tens of thousands to install.
Instead the "last mile" should be a non-profit funded by ISPs who lease the channels. The non-profit is responsible for installing the "last mile," upgrading it, and repairing defects in it. The ISP is responsible for everything that happens from the exchange upon up (inc. pricing, support, peerage agreements, interconnects, etc).
This way you can still choose Comcast if you wish but may also have several local ISPs competing for your business. When you choose to change no engineer needs to come to your house, they just plug and unplug you at the exchange.