Almost all regional sports nets are wholly or partially owned by Fox and/or Cablevision, two huge "enemies" of Dish. Yet, Dish somehow manages to carry most RSN's in America. Of course, they aren't the "enemy". They are both COMPETITORS and BUSINESS PARTNERS at the same time.
That being said, the owner of YES (an RSN that Dish doesn't carry) is indeed an enemy. Not of Dish. But, of the sport of baseball itself.