If Roku is being truthful about the reasons for their disagreement with Google (YouTube), I take their side. As to Prime, I don't think there's anything set in stone about that. Perhaps Amazon will also pull their content.
But remember one thing about both Google and Amazon. They both sell competing hardware, as well as being content providers. Certainly they'd prefer you buy their hardware over Roku. Personally, I hate the Amazon-centric user interface of the Fire TV. And the Google TV user interface is annoying as well. I have it on my Nvidia Shield players, and I hate the way they've taken over the home screen.
It's entirely possible the government will have something to say about unfair practices by restricting where their content is available.
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