It does seem to be a word game, because "it's not stopping any bullets" either isn't honest (it does stop bullets from hitting you when the enemy doesn't know where to shoot) or it's limited, just like obscurity is ("it may stop a few bullets, but it won't stop all, and there will be other weapons it can't stop either"). I think public key exchange is considered security, but it still requires to obscure your private keys.

Perhaps a better word would be resistance (to intrusion), which is a dimension orthogonal to visibility.