No chance. When you're a legal eagle like Angelos you can do this...all perfectly legal. He was able to extract this deal from the Lords of Baseball - he had a unilaterally declared exclusive zone which included DC and Virginia, and he was threatening litigation to enforce that self-declared exclusivity. Not only was it a matter of the mortal dread that sports leagues generally have of the law courts, but (1) they knew there is no way Angelos can lose in a Maryland court, and (2) there was the threat to force the owners to open their books (something the Orioles don't have to do since lawyers don't have to open their books to anyone) - so they acceeded.
Doesn't mean it doesn't suck though...in an earlier era we used to call this 'blackmail'.
I am not sure you mean or are implying with the term "unilaterally declared exclusive zone" - the territories are prescribed by the franchise agreement MLB and the team (Orioles, in this case). That agreement says that teams have exclusive rights to the town/city/municipality that the team is located in (in this case, Baltimore) and any city/county that is touch by the team's home territory. So, the O's have rights to Howard County, but not PG County. MLB could not put a team in Howard County, or in Balto County, without the Orioles' permission.
The TV rights are a different agreement and I think had MLB stood up to the Orioles and enforced the MLB interpretation of tv territories and the purview that MLB has the right to divvy up the territories, I think that MLB would have prevailed.