Personally, I think it's an issue that should fall under the legislation and authorities that deals with antitrust and with censorship. However, the big unspoken motivation behind network neutrality is people's perceived human right of having access to pirated entertainment media. This whole thing started around 15 years ago when broadband networks weren't and still aren't designed for peer to peer sharing of entertainment media, the impact this had on the networks were significant. ISPs had to deal with this because of the impact on their customers, as anyone would know who shared a contented connection with people who had a peer to peer piracy addiction in those days. This was before the time of most legitimate means we have nowadays to obtain entertainment media over the internet, before Youtube, iTunes video, Hulu, Netflix, etc.
The issue is that peer to peer sharing of sharing of pirated entertainment media is not protected by antitrust or censorship legislation, so a 'third way' had to be found, some kind of overriding principle that even trumps copyright law but without mentioning it. That's net neutrality, which I think is redundant now because there are many legitimate and affordable ways to get entertainment media and the networks can easily handle multiple forms of high quality streaming media, but the political momentum behind network neutrality is still there and exploited by some content providers for their own gain.