Exactly the opposite is true. NN is most important when you have a market dominated by a few large companies!
In Europe, we don't have net neutrality. It's common to see plans marketed with free/unlimited data favouring specific services, such as Netflix.
But neutrality just isn't a big issue so long as there is plenty of competition among providers. If one company is giving slow speeds (or high charges) to your favourite services, you just switch. There's plenty of choices.
Surely the real issue in the US & Canada is the limited competition among monopolistic carriers and service providers. Net neutrality is just a smokescreen!