The "low powered hardware" is why I always buy an external streaming device. I started with the original Apple TV, then a bunch of Roku variants, when Roku got unreliable, I went back to modern Apple TVs. They just work better. I've had sales guys in stores get really pushy with me about "you dont need that", one time I finally had to say to one of them "I get it, I don't care that its already in the TV, I'm buying the external box, either from you or from another store so stop arguing and just sell it to me".
Absolutely. I do the same. IMO it's either Apple TV or Nvidia Shield. Everything else is hit or miss (likely miss).
From a developer's perspective, it's a nightmare to deal with such hardware.
As an outsider, the fact that cross-device stuff just works in apple's ecosystem is probably the biggest thing I'm jealous of. It's crazy that something as simple as screen casting is still hit or miss when it comes to (android / linux) <-> (web os / chromecast / fire stick)