An interesting, albeit misleading statistic. What's the rate of 4K display adoption among homes that have or are in the market for a streaming appliance like the Apple TV (1080p), Fire TV (4K), Nvidia Shield (4K HDR), Chromecast (4K), or Roku (4K)? Apple is way behind the curve compared to competitor devices and their target market for the Apple TV is much more likely to have or want 4K than the general public.
Misleading is assuming Apple is going after bleeding edge adopters. It's become increasingly apparent that Apple is ignoring the "Pro" market and has instead started targeting the least common denominator. It's unlikely to see Apple take action before the market has reached 51% of NA homes.
You can also expect to see the iTune store / iDevices support 4k with the appropriate hardware and content as well. You wont see a 4k Apple TV come before Apple has rolled out its own 4k content library.
Currently 4k adoption is between 10 - 20%.... it's projected to hit 35% some time in 2019...
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