In these cases the undercover cops often set a meet and then arrest the perp when he shows up at the designated time and place.
The crime is “soliciting” not performing sex acts with the teen.
Obviously “soliciting” is a more minor offense that doing the deed.
You could make the same argument for “soliciting” a murder for hire—the deal has technically not been “done” until the cash is paid—but obviously you want the cops stopping the murder before it happens—rather than waiting until afterwards and then making the arrest because now they can “prove” intent.
Again,,I disagree,,,seems more like the cops are soliciting to me,,or at least entrapment.