Xbox is fun example because they hit some peaks and then actively got worse. The Xbox 360 was somewhat focused on being your living room hub and for many years tried to actually get people to use Windows Media Center, and supported its own and general Media Center remotes. (I used it for streaming some things.) It also had a bunch of support for many TVs that used custom HDMI protocols (pre-HDMI-CEC).
The original Xbox One with bundled Kinect was the peak of their integration attempt before "gamer outrage" crippled and then killed its efforts. It supported HDMI-CEC some but it also truly had "universal remote" capabilities as it could use the Kinect's IR depth sensor as an IR blaster to send commands to almost anything that uses a traditional IR remote. It had a big database of IR commands and also could use the IR depth sensor to watch and try to learn any IR remote you pointed at it. On top of that it also had a port on the back to connect a normal IR blaster if you needed to send signals to hardware that wouldn't catch a blast from the Kinect or just wanted to disconnect the Kinect for a bit but still have TV/sound system/cable box control.
That Xbox One also had an HDMI passthrough and could picture-in-picture with something like a cable box. (It also support picture-in-picture from some apps at the time.)
The original on-device-only voice recognition with the Kinect was great and "Xbox, Volume Up" was something I used all the time on the original Xbox One until Cortana took over the voice recognition and made it far more cumbersome.
The OneGuide was an interesting attempt to show you a mixture of your TV/Cable grids and highlighted content from streaming apps you had installed. It would let you jump to channels on TV or Cable just as easily as launching something like Hulu straight into a show.
Almost all of those features were eventually shutdown or left to slowly break in the drastic post-launch retooling from the "gamer outrage" that the Xbox One was "gamer-focused enough" and their pressure that the Xbox should be "only for games". (The Xbox One and Xbox Series still support rudimentary HDMI-CEC, but in my experience it is hit-and-miss and definitely nowhere near as well supported as the "universal remote" stuff.)