The symbol appears (to me) to be deliberately designed to be easy to disguise with a wave or other subtle hand gesture, particularly on some sort of video call.

The symbol appears (to me) to be deliberately designed to be easy to disguise with a wave or other subtle hand gesture, particularly on some sort of video call. It's very obvious from the front, but not very obvious from other perspectives. It's this information differential that makes it effective. If you are at the point where you cannot even get your hands near where other people can see them, your signal bandwidth to the outside world is likely already severely curtailed. As in, you are probably locked in a basement. I don't think this is meant to address that severe of a human trafficking/abuse situation.