A person presumed to possess the legal capacity for consent cannot have sex with a person presumed to lack that legal capacity. The teenager is not restricted; the adult is restricted.
When a camera is added, the law becomes inconsistent. The minor lacks the capacity to legally engage in sex, but is now (potentially) culpable in their own exploitation if they video themselves.
A person presumed to possess the legal capacity for consent cannot have sex with a person presumed to lack that legal capacity. The teenager is not restricted; the adult is restricted.
When a camera is added, the law becomes inconsistent. The minor lacks the capacity to legally engage in sex, but is now (potentially) culpable in their own exploitation if they video themselves.