Back when this list was young we used to have discussions about a la carte cable quite often. One poster, who is no longer in the group, made the case that in order to implement a la carte a cable company would have to change its accounting from account name and tier to account name and a string of all the channels with yes/no flags attached to each. Then they would have to make a system for the consumer to change which channels they want and figure out how to bill for changes between billing periods. Not only could they not raise rates to pay for designing and implementing such a system, the result would be lower monthly income. The choice not to even think about a system like that made sense - the PR people from the cable companies might have blathered that the tier system was there because that's what people want, but there wasn't enough pressure to change and they didn't.
As internet speeds increased and TVs became smart TVs streaming looks to be the future. I don't know what percentage of US homes are accessible to cable and not to broadband internet and that might be enough to keep cable viable even as people with broadband cancel their cable subscriptions. Streaming is not channel dependent and outside of live events can be all on demand. The transition of the business model from networks and cable companies to a subscription model will be hard and the companies that will end up losing income will fight it in every way they know how but streaming on demand programs will be the future.