Net neutrality would not suppress ISP competition in any way, shape, or form. Unless you count upset ISPs trying to take their ball and go home, like spoiled children.

And yes, robust ISP competition would be awesome. But there are parts of the country that realistically could not support more than one ISP. Do those people not deserve neutrality in their internet service? What do you say to them if their ISP suddenly decided to fuck with their traffic? There would never be anyone else to turn to.