Net neutrality is about the desire of ISPs to get paid from both ends of a connection. ISPs want to get money from consumers for getting access to content producers and service providers and from the latter in turn for their content being made available to consumers. The current system is that ISPs are just being paid by consumers for access to what's put online by content and service providers. Content and service providers get access to consumers for free right now. This plan by sprint limits access to consumers of this kind of connection to a single service that the consumer opts into. It seems relevant, but I'm not sure. Would net neutrality regulation prohibit something like this?
Yes, because net neutrality is mainly about selling only "the Internet" and giving equal access to all websites to all customers.
You are hearing more about the connection-throttling issues Netflix has with Verizon currently, but it ultimately falls under net neutrality too, as Verizon is trying to de-prioritize connections to Netflix.