tl;dr: It’s another instance of the government butting in with a cure worse than the alleged disease:
Simply put, net neutrality is the principle that all traffic on the internet should be treated equally. So your internet service provider, under a system of net neutrality, isn’t allowed to send some kinds of data to you faster. It has to treat everything the same—even if you wouldn’t mind, for example, slower emails if it meant smooth HD video on YouTube.
It also means that no one can pay to get their services to you quicker: Amazon can’t make its on-demand video services more attractive by outbidding Netflix so it can stream to you in higher quality. Finally, all applications and websites are treated the same—so if your internet connection is choppy, your service provider can’t prioritise Spotify to ensure smooth music playback.
In other words, it’s a bit of a drag. It limits a service provider’s freedom to operate their networks as they see fit, to provide customers with the best service, and it stops those providers offering higher-priced packages to heavy data users so they can enjoy a fast lane for Netflix without slowing down their neighbours’ connections. Product differentiation is one the main ways companies compete with one another, and providers will be denied that if net neutrality becomes law.
So why do so many people treat net neutrality as an article of faith? Well, the clue’s in those last three words, because most of the arguments in favour of neutrality have a suspicious ring of dogma about them—and most factual claims offered up to support neutrality don’t entirely stand up to scrutiny.