you sure? anynet+/hdmi-cec has been around since quite some time, most people just don't know about it as it's usually poorly documented and buried in not so user-friendly config menus.
Sometimes it doesn’t work due to manufacturer bugs. I have a TV that has a bug in their implementation on a specific series of theirs where it won’t turn on/off the TV, but volume does work via HDMI. From doing extensive research I’m not alone.
That being said, Sony just released an update to tons of their devices that fixes a bug where this functionality never really worked. The standards are moet certainly there, but getting manufacturers to implement them well can be quite the challenge.