It's a cycle that everyone is caught in. The production companies need to have a large suite of channels so that they have bargaining leverage over the content delivery services (Comcast, AT&T, FiOS, YouTube TV, etc). The content delivery services merge so that they can have bargaining leverage over the production companies. It's very hard to make an economic case for a la carte if you are a production company because you will lose this leverage.
Even Netflix is not immune from this... they stick with the package deal as well, rather than the Amazon/iTunes/Pay Per View model. And look at their success! It even spurred the crusty old broadcast production companies to work together to put together a similar offering via Hulu. Amazon similarly needed to move away from a la carte with it's "Prime Video" service, and now Apple is making a similar move.
We are moving AWAY from a la carte, not toward it - and it seems to be a fundamental artifact of copyright law, not something that is going to change in the short term. Those of us who like a la carte are stuck with usenet or torrents.