DISH might be on to something with being a one-stop location for all non-sports programming....I think people would prefer that over signing up for several different services, and having to keep track of different bills. Problem I see is that a lot of the programming they'd want to offer is for channels owned by companies that have made huge investments in sports (Disney, FOX, Time Warner, Comcast). They may not want to offer any of their channels....especially Comcast who is also a distributor, and I would think they'd offer their own OTT service before licensing them to DISH under those circumstances. I do think DISH has something up their sleeve though (besides just SlingTV). With all the wireless spectrum they own, they have lots of possibilities and make an attractive partner for someone already in that business.
Legally, providers need to give carriage for must-see programming while stations can't deny providers must-see programming.
For example, Comcast didn't want to broadcast MASN because Comcast felt that they had the right to the programming and not MASN. Comcast has a strong position in this market and if they don't carry your station then it dies. So, their plan was to refuse to carry MASN, let MASN die and then buy the Orioles/Nationals media rights at a discount. MASN sued and the courts told Comcast they can't pull that.
On the other hand, CSN Philly isn't broadcast by DirecTV or DISH. Those two broadcasters sued for the rights and they originally lost due to some crazy technicality that only applies to that station. But in general, that doesn't work.
This basically means that it will be hard for DISH to refuse to carry sports and for Fox or Disney (Comcast would be fine with it) to refuse to provide them carriage to other stations. Which means that the courts would need to get involved. But money is a reason to refuse to carry a station and RSNs are getting more expensive. If they divest of their own RSNs then it's not like it would be because they're biased.
Dish would have a winning case to demand carriage for other stations and would have a strong case to refuse to carry RSNs on the basic tier. It would be decided in the courts.