Big Hollywood wanted a do-over on vertical integration, after the government made them give up their theater chains in Ancient Times. Since government regulators weren't stopping them from setting up their own streaming services, it seemed like the perfect opportunity to right the wrongs of history.

Probably the biggest payoff has been weakening Netflix as a streaming competitor. But this has mainly benefited Amazon, which actually has the war chest to keep competing with Netflix and with everyone else.

Sony is smart enough to stay out of this fight, and spend its money making content that other people want to buy.