Would like to add my interest in this. The lack of ability to turn on my 55” HiSense Roku TV via IP is what has stopped me from buying a second one for my house. I measured my TV and it uses 67 watts on and 17 watts in light sleep mode. This is really too much as it seems light sleep mode does a lot of things other than just listen on Wi-Fi. To make up for this missing functionality I end up buying the iTach WF2IR which is an always on Wi-Fi device that sends IR. This device uses 2 watts.
It may be that just some hobbyists are asking for this feature now, but the connected home is becoming a reality and Roku TVs will fall behind if they don’t build it into their design. Also it is unbelievable that the relatively new roku 4 does not support CEC control like Chromecast does. Ignoring home automation/internet of things could be the reason Roku loses its top spot in streaming, getting passed by someone who is looking towards the future.