Not sure why this is being downed. I haven't looked into the details of this case, but the more detailed the wireframe mesh the faces are being fit to, the more possibilities there are, and the lower the likelihood of collisions between two people. Think of it as a hashmap with the number of buckets being determined by the mesh quality. At a certain point, a few collisions won't hinder apps from capitalizing on the information.

Apple is very popular among the HN crowd. Any comment critical of Apple or skeptical of their intentions will be immediately rejected by a substantial number of readers.