You can do this without killing the ISPs even. The municipality can own the cable in the streets and on the poles, and bring it back to a POP where different ISPs can connect in. You want to switch from comcast to verizon? Someone moves a cable in the POP, and it's done.
I think this is the logical next step, as it'll be a bit easier to do this without the ISPs lobbying it away. (but still nearly impossible)