There could be 1 service that carries all the content and the companies that produce that content can still be paid without having to subscribe to 10 different services to get all the content you’re looking for. Like how Netflix worked before everyone decided to make their own platform and took damn near everything off Netflix.
There could be multiple services with the same content that compete on pricing or other services/features instead of holding content hostage.
Since they all hold different things hostage, you really do not have a choice where you watch the show/movie you want; it’s only on a specific service that has it.