Don't expect a Ferrari for Ford Focus money
I have also been using car analogies when describing the state of the ATV and tvOS.
I agree with your comparison with the ATV4K to a Ferrari, but I have a different point of view on the matter.
I think the ATV4 is the best streaming box out there, and very powerful. The problem with it is that Apple has done very little to encourage developers to utilize the power of the ATV4K.
Especially at the beginning of the tvOS, Apple seemed to put roadblocks and obstacles in the way of developers that would potentially make the ATV more that just a streamer box.
While some of the roadblocks and obstacles have been addressed, any momentum the ATV had going for it died.
Because of Apple actions, the current state of the ATV4K is that it is an overpowered, but very expensive Netflix and HBO streaming box.
It is much better than the cheaper streaming boxes, especially with the tvOS UI and AppStore UI, but once you get into the apps, they are now mostly universal across all platforms.
The power is mostly wasted.
Now for my analogy: The ATV4K is like buying a Ferrari to do grocery runs. It will sure perform better than using a Ford Focus, but the cost of the Ferrari might not be worth the current use of it.
This is especially true for secondary televisions, like bedrooms and guest rooms.
Why spend $200 for an ATV4K for a smaller TV in a room that it wouldn't get utilized as much, when you can use the built-in a Smart TV apps, or a cheap FireStick? The apps are basically identical, why not pay a fraction of the price of an ATV, and get a mostly identical experience when it comes to the apps?
This is were a cheaper ATV would come into play.