You couldn't run Plex on the ATV 1-3, which was the point my last post was responding to as it was a main reason in me thinking it was worth upgrading.
I have an extensive purchase library of iTunes movies so all those other devices are not something I could consider. Yes you could argue that I have become a slave to and tied myself to Apple devices by purchasing so much iTunes content, but the fact is that is the ecosystem I have chosen to invest in and, for me, it works.
I'm not saying the Apple TV is the best choice for everyone, it is quite a niche device compared to some of the ones you have listed, I won't deny that. But if your primary movie/tv consumption is iTunes then its the best device for you.