Why can’t Google and Roku match the Apple TV?

A recurring thing I’ve seen online is new Apple TV 4K owners exclaiming how happy they are to have made the switch from another platform. Usually that means Google TV or Roku, which are preinstalled on many TVs, or else available through add-on devices. They’re likely to be ecstatic if they’ve switched from Amazon’s Fire TV, which is functional, but not much more than that — I doubt few people purposefully buy a Fire TV set unless they’re deeply embedded in the Amazon ecosystem.