I'm largely opposed to the FCC's open internet order, so I'll weigh in.
First, it's essential to distinguish between the concept of net neutrality and the FCC's 2015 Open Internet Order. Net neutrality, in the sense of ISPs acting as "dumb pipes" that treat all traffic the same, is basically how the Internet has functioned in the U.S. since the rise of broadband. In fact, one of the reasons we have net neutrality is that it's what consumers wanted. In the early days, services like AOL and Prodigy didn't just provide you with web access so you could go wherever you wanted. They were providing a curated internet experience, both because people didn't know how to use the Internet and because the ISPs thought that people would prefer an Internet that acted more like TV. The demise of those services has a lot to do with the fact that consumers preferred an open internet.
Now, in the last decade or so, there have only been a few documented instances of ISPs violating the principle of net neutrality. There are probably more instances that aren't widely known, but it's certainly very rare, and when it has happened, there has typically been a swift legal response and public outcry. So the second thing to understand is that the rules are about preserving the status quo. Anyone who offers a parade of horribles regarding the repeal of net neutrality rules is full of it. Nobody really knows what's going to happen. On the other hand there is some merit to the idea that ISPs have been afraid of violating net neutrality as long as the FCC has been considering the issue, but that if the Commission repeals the rules, it will be like finally giving the ISPs clear permission to violate net neutrality.
The flip-side of regulating to maintain the status quo is that we also don't know what good things we might be missing out on if ISPs and edge providers were allowed to experiment. There's a growing body of economic literature recognizing that there can be efficiencies to two sided markets (e.g., a broadband market in which the ISP can charge both the end consumer and the content provider for the service of using their cables). For instance, Spotify and T-Mobile came up with a deal a few years back to provide unlimited data for streaming music. Consumers loved it, but net neutrality warriors flipped out. Their reasoning was basically that a hypothetical upstart music service wouldn't be able to afford to subsidize its users' data, or at least such an upstart wouldn't have the scale to negotiate with a big company like T-Mobile. But those kinds of barriers to entry exist in EVERY market. It's the reason we have big companies--they have the scale to efficiently provide products and services that people want.
In the short term, the likely "violations" of net neutrality are all likely to be in terms of streaming video and music services. That's what the ISPs are concerned about. The real problem is that some portion of broadband users are consuming almost all of the broadband in the country so that they can watch Stranger Things. A lot of people are subsidizing the internet usage of a lot of other people. You might say, then why not just charge people for the amount of data that they use? Well, it's because research has pretty clearly demonstrated that consumers don't like being rationed. They hate having to watch their consumption of data or not knowing what their bill is going to be. They would much rather have a known, up-front expense that can set on a recurring basis and then forget about. Two sided pricing gives the ISPs a way to do that. If they charge Netflix and the other big users, then that price gets passed on to the consumer via higher Netflix fees. The result should be lower baseline broadband fees for everyone, with the people who use a lot more bandwidth paying for it via their content providers. (In reality, it's more likely that broadband prices won't drop so much as they'll stay level for longer than they otherwise would.)
There are a few other possibilities that the net neutrality people have raised, but I think they're pretty unlikely. First, the idea that we're going to have some sort of 1984 political censorship is pretty fancifal, in my opinion. Most broadband infrastructure is owned by publicly-traded companies that are interested in maximizing shareholder value and revenue, not grinding a political axe. The other is that the ISPs will offer their own content and steer consumers towards it, away from competing content. That's more plausible, but it's very likely already illegal under the FTC Act and possibly the Sherman Act.
Finally, I want to address the argument someone made that Republicans opposed to net neutrality have only one argument: regulation is bad. I'm no fan of congressional Republicans, but that argument is better than it sounds, especially if we keep in mind that this is a regulation to maintain a status quo that existed even without regulation. The free market is infinitely creative--far more than regulators. The innovations that the free market comes up with can be categorized into three buckets:
(1) New ideas that are bad for consumers, but which the market can sort out. E.g., New Coke. People don't like it, but we don't need regulation to outlaw New Coke. This is by far the biggest bucket. Capitalists are coming up with terrible ideas constantly, and most of them are utter failures.
(2) New ideas that are good for consumers. Someone invents a better mousetrap. He gets rich, we get to kill more mice, and everyone is happy. This is a smaller bucket, but it's where the magic happens. It's why we live in such a tremendously prosperous society.
(3) New ideas that are bad for consumers, but which the market cannot fix. E.g., air pollution. Every capitalist has an incentive to burn cheap, dirty fuel, and not to invest in equipment to reduce emissions. The costs are born by the public at large, so there's a market failure, and regulation is necessary to address the failure. This bucket is by far the smallest of the three.
My view (and the view of most economists), is that we shouldn't regulate unless we're in bucket three, and we should be fairly certain that's where we are before we act. There are three main reasons. First is that bucket three is the smallest, and even though regulators have a tendency to see everything as a problem that requires regulation, the reality is that far fewer things are true market failures. The second reason is that a false positive is durable. Once we pass a regulation, it's there until it gets repealed, even if market conditions change (which they always do). The third reason isn't always true, but it usually is: We can typically adopt a wait and see approach. If a market failure materializes, we can regulate, but if we regulate first, we'll never really know if our intervention was necessary. (There are admittedly areas in which the risk of allowing a failure might be so great that we step in regardless.)
So for me, the bottom line is that I'm slightly inclined to think that net neutrality rules will do more harm than good, but I'm far more confident that this is an area where we should be reactive rather than proactive.