Switching frequently between service is exactly what the companies don't want. I agree that this might be where we're headed, but the idea of a subscription is to have a recurring and predictable stream of income.

The best solution for the content industry as a whole would be to set up a clearing house, that provides access to all movies and series, streaming services should then be able to purchase the content they want on their service. That would allow the services to compete on the quality of their service, not their catalog. Let's face it consumers don't care if Star Wars is created by Disney or Warner Bros or that Breaking Bad is distributed by Sony.