Amazon, like Apple, has plenty of money to pour into entertainment if they decide they want to. But if it's not profitable why should Apple keep spending on its own service? Netflix, though, is in the biggest trouble, I think; anecdotally people seem to think of Amazon and Hulu content as better-quality on average than Netflix. Disney is spending a massive amount of money on its upcoming original shows obviously trying to compete with Amazon or maybe even HBO. (And meanwhile who knows whether Warner has any idea what they're doing with HBO - look at their DC Universe compared with Marvel.)
In the end it's an amazing time to work in the entertainment industry. And to pirate media.