If you had to give away your privacy to use one and could only use helmets authorized by your motorcycle dealer you might have a point. We accept impositions on our freedom all the time when what we get in return is worth the sacrifice. If signed binaries actually delivered on their promise of keeping people safe there'd be a discussion that could be had on whether or not it'd be worthwhile, but since they don't actually protect people we'd be giving up our privacy for nothing.