The only reason there isn’t a problem right now is because telecommunications providers have been kept in check by the threat of net neutrality legislation. As soon as the debate is settled and net neutrality legislation is taken off the table, there will be a very real problem as telecom giants establish themselves as the gatekeepers of information and competition.
Regulating in such a way that legislation is only put in place to respond to clear problems is far more expensive than taking a proactive approach. Surely preventing a future problem is preferable to waiting for the problem to occur, bringing with it all the economic and social impacts?
It is also misleading to suggest that there is/was no problem before net neutrality. Before net neutrality laws were passed in the US, six internet providers were accused of degrading internet quality and services for companies, deliberately harming the business and the quality of service it could provide to its customers.