It is simple as this:

If you give control over who can when access which information or if certain information are accessible at all, into the hands of an non-democratic entity (e.g. corporation where majority votes by employees don't mean anything last time I checked), guess what you get …

So unless you want to eliminate the real freedom that the Internet made possible, you better be for Net Neutrality.

To get an idea how it looks like, if you got it all wrong, just look at Copyright and traditional media today. Copyright restricts creativity and is often used (not intentionally necessarily, but as a side effect) to control distribution and availability of content and information.

That's literally censorship and if control is consolidated far enough, then you can do really funny things, such as rewriting history and oppress people, by using partial truth and manipulated images to sell convenient lies to them.

Okay, social media turns this brave new world up site down and the majority of the population into criminals, but this whole mess is not sorted out yet. … well, different subject, but somewhat related