It’s not libertarians pushing, it is everyone who fears being shut out by the providers. The problem here is that Congress allowed monopoly over the last mile. Phone companies, Cable companies pretty much control the pipeline to your home. This scares people like, say, Apple and Google and Amazon and media manufacturers like Disney and folks who make entertainment. Theoretically, your cable company (mine is Time Warner) could cut deals that favor some content over others and even prohibit some content. Not sure what the solution is. I favor property rights but these entities have monopolies.
The ISPs don't have legitimate "property rights" over something the government gave away to them. For example, I didn't have any say over Verizon running a FIOS line under my driveway to reach the rest of the houses on the street -- if it were a true "property rights" issue, I could tell them to get lost or make them pay whatever price I saw fit to dictate.