I think they may be getting the same lesson the Music industry learned.
The product is expensive, the work to make it more expensive than it has to be, and many consumers would like to pick and choose which teams and sports they watch rather than buy a large mixed bundle of sports.
The music industry (for example) worked to make their product expensive -- you had to buy multiple songs.. not just the one you wanted.
The major ESPN channels are bundled into the almost all cable TV packages -- making them (those packages) very expensive -- for those who don't watch sports; this is also hiding the real cost(s) of sports from those who do enjoy watching them.
As more and more folks cut the cord, ESPN is going to lose out nearly every time.. and I'm sure that is a large % of the reported drop.
Even YouTube which is a "live" TV bundle coming to market, is including ESPN. Often companies that have sports properties like ABC, "require" cable TV companies into include their sports channels in most bundles -- giving them high subscriber numbers and gaining revenue from nearly every cable TV home.
The MSO - Multi System Operators -- have insisted that this bundling makes it cable TV cheaper for everyone -- it can't possibly help folks who don't watch sports.
While I know some sports fans who like and love nearly every type and kind of sport, not every fan loves every sport.
Since today any of the sport leagues can easily offer direct to consumer programming -- networks that offer sports programming, are really only provided 1 limited function -- ad sales. Having multiple companies bid for sports programming has certainly helped drive up the price over the last 30+ years.
I would think however, a direct to consumer model, that perhaps includes little or no advertising as well as other offerings that are contain large amounts of advertising... would in the long run get the most value for the teams and owners.
TV production from remote locations in teh 1950's was fairly hard. It's not super simple today but it is far easier and teams and leagues would be better off producing their own content and then selling the programming direct to consumers.