Where I'm from (Russia), we had (and still have, to a some extent) a lot of competition in ISP space. This had happened just because government weren't particularly looking at that direction at the time (90s and early 2000s).
If one ISP did some weird stuff that upset customers, the market had actually worked and they lost profits, making them reconsider. This may sound weird, but that really was like that - "power" users were vocal, and word of mouth did spread fast. And absence of NN allowed ISPs to do things that were actually beneficial to the customers, like routing specific traffic differently so e.g. gaming would be smoother and files would download faster. Just because content customers meant good reputation - a stable userbase with steady growth. So I don't believe NN is a good idea if the market's right. It only makes sense if it's bad, with a few giant telcos and no competition.
[Edit: ignore this paragraph, please. I'm keeping it, but indeed it's a long stretch.] When the government decided they're going to get a grip on the tubes, things immediately got worse. No NN here, though, just censorship - a great pile of unsound kludges with mandatory monitoring and automatic fines if something goes through. But NN here would've killed tiniest ISPs just as well.
That's just how I see things. It very well could be that I'm mistaken here.