Basically without net neutrality, ISPs could promote their own content services while denying other content providers from putting CDN nodes on their network.
They could throttle bandwidth to some content providers while providing a "fast lane" (non-throttled) access to others.
It would allow them to block services all together.
They could get very creative in their ways to pushing you to certain services depending on which content providers pay.
So, your internet will be your internet, but if Netflix decides not to pay, then the ISP would be able to throttle your connection to Netflix servers thus degrading your services to Netflix, then they would blame Netflix for your sh1tty connection to it.
Net neutrality is better for everyone except for the ISPs because without it, the ISPs can (and will) multi-dip at every opportunity they get while throttling non-payers so they will not tax their systems, which will give them no motivation to upgrade their networks.
You as a consumer want net neutrality.