The predictions that came from the alarmists turned out to be false - which makes me think there is an ulterior motive behind NN we are not being told about.
I'm not sure you can infer that because the worst predictions of alarmists didn't immediately happen, there is no danger in not having network neutrality.
Assuming an ulterior motive is unnecessary, the stated motive seems good enough, they don't want a network to freeze out their services in order to promote their own.
NN doesn't prevent a carrier from offering a plan with Unlimited* data where the asterisk means "up to 25GB at maximum speed, lowered to 128/64 Kbps after exceeding the limit, until the end of billing period".
It would prevent the carrier from not counting certain traffic in the data usage or not limiting the speed of some traffic after the data limit is reached.
From what I remember, the crux of the matter was that the change of regulation would give more negotiating power to ISPs when it came to common infrastructures they shared with large cloud providers (Google and co).
The status quo was highly advantageous to said cloud providers, which is why they lobbied so hard against net neutrality changes. And since people on the internet get really vocal about perceived threats to the internet, the lobbying went viral.
Assuming an ulterior motive is unnecessary, the stated motive seems good enough, they don't want a network to freeze out their services in order to promote their own.