Good point. But also consider the same thing can happen on the other extreme.

For example say that internet service provider gains a monopoly through its cheap service. Now it can unfairly suppress new search engines by only allowing Bing.

The thing about the net neutrality law would be that it is equally applied across the board. As long as it doesn't unfairly benefit a specific group, it's fair. And it benefits people in general because it prevents companies from leveraging power from short term tactics which have long term negative repercussions on society.