[noggin]

One other thing to consider, independently of CEC, is that some TVs have an IP remote control solution implemented.  My Sony TV can be controlled over IP (cabled or WiFi network connection) - so you can change channels, change volume, change HDMI inputs etc. using commands sent over IP.  I believe other manufacturers also support this too. (ISTR that Sony have a couple of different supported methods for doing this).  CEC is a neat solution too - but it may not be the only one.  (Software like Home Assistant supports various manufacturers IP protocols, but you can also find small command line utilities if you google.  The same is true of many AVRs)