The last renovation that Apple TV received was at the end of 2015, with the launch of the 4th generation Apple TV, which hit the market 3 years after its predecessor, a time when it seemed that Apple had completely abandoned this set- top box. During the first days of availability, many experts claimed that this device had a version of HDMI compatible with the reproduction of content in 4k, but Apple had capped it so that buyers could not use it. Presumably in time, Apple could release an update allowing this use. But it seems that it will not be like that.
According to the latest rumors, Apple is working on a device that is codenamed J1o5, a device that would be the fifth generation of Apple TV and that would finally support content in 4k resolution. The guys from Cupertino recently hired Timothy Twerdhal, an engineer who had previously worked on the development of Amazon's Fire TV, which suggests that Apple wants to focus on this device again in a more responsible way than before.
This fifth generation would not offer us radical changes neither in its design nor in its functions, but it would focus on offering the reproduction via streaming of content in 4k and perhaps an application of the internal storage space of the device, which is currently available in 32 and 64 GB. Presumably, Apple should launch some more feature so that current users of the 4th generation Apple TV think about it when renewing their devices with this new one, which could arrive before the end of the year.
I think that the current Apple TV has a lot of room for improvement, both in Apps and in TvOs improvements. Although Apple will do what it wants even if the only improvement is to be able to stream 4k content (which, currently only a handful of people would take advantage of). Those who had netflix and 4k TV would be the most graceful.
I also understand that they will put a new more powerful chip with more RAM? and higher capacity (128gb - 256?). Making these updates to your set-top box in such a short space of time and seeing how the updates work in Apple for a few years (where the older terminals are dragged with the latest iOs) seems to me a dirty thing to leave an AppleTV4 "useless" with a supposed TvOs 11 that would only perform well in that supposed Apple TV 5… .. At least I, I do not buy Apple TV every 2 years, So I hope they get more juice from the Actual and have decent updates for several years.