As much as I dislike mandatory certification, I can understand the need for it in wireless battery powered devices: a malfunctioning decide can talk the battery life if everything within range, and most consumers aren't equipped to realize that this is happening much less identify the device that's causing the problem
Perhaps the solution is to make the spec open but make using the trademark contingent on certification (much like USB, for example)
Maybe I'm making some category error here but I can think of dozens of protocols that do not require certification.