I believe the argument is been long over. People in the know prefer to buy a "dumb" TV and add the smarts as needed.
Apple business model is to lock you into their eco-system. I have noticed lately with the updates that they are pushing this, "Start Playing on device 1" then seamlessly "move to device #2 and continue," and they can do that without having to sell you their own TV.
If you currently can do everything in Rokus/Amazon and don't need/want any of the Apple's features then fine, live happy with your purchase, but someday, somehow, there is a feature on the Apple eco-system that will pull you in and at that time, they got you.