As I stated in several earlier threads, the AppleTV would be an ideal HomeKit controller/server.
Consider: you were out and about with your iPhone running HomeKit -- as you approach home, you want to turn lights on, unlock the gates, open the garage door, etc.
Simple, Right? You just use your iPhone to send the commands to ... to ... to what, exactly? To your router? To each accessory?
That means, the control codes are sent in a way that anyone can intercept them...