Competition drives innovation, but also, we've generally seen that things like municipal broadband are _more_ innovative than an incumbent monopoly carrier. Large chunks of the US don't have much competition at all in wired services, and if we approach that in wireless, we are likely to see the same effects starting where the local monopoly tries to extract maximum dollars out of an aging infrastructure. Lookin' at you, Comcast, lookin' at you.
As you say, "incumbent monopoly carrier" is not competition, so a municipal provider which competes with broadband is a great idea. This article, however, is arguing we don't need more bandwidth, and we need more consolidation of major providers: I'm not convinced.