An interesting omission from the movie

I warn you in all fairness, there are spoilers are ahead.

Diana gets Steve back the way I expected she would, once I saw the trailers and it was clear that the film's villain had the power to grant one's deepest wish. She also had to let him go again, the way I expected she would, because it was necessary to defeat the villain. But it's interesting that Diana doesn't let Steve go because, thanks to her, he essentially stole someone else's body. In fact there is not one scene where she grapples with the ethics of that situation.

When you see the movie, you see that at Diana doesn't recognize Steve at first, because his consciousness has simply been poured into the body of a man of 1984 who was presumably about the same age as Steve when he died. Steve takes over that body and the man whose body it was -- his consciousness at least -- is simply gone. Chris Pine replaced the actor portraying that body for the film, and this is justified by Diana telling him "all I see is you," when he looks in a mirror and sees that other man. When Diana has to renounce her wish, both because that's the only way to beat Max Lord, and because having her wish granted has come at the cost of much of her power -- leaving her outmatched by Cheetah -- Steve goes away again and the original consciousness returns to its host body. But Diana only renounces her wish to have Steve back because she has to in order to beat Lord, and to get her power back. She only lets Steve go again with the greatest reluctance, and if that hadn't been necessary, it's clear she would have kept Steve with her to live out the remainder of his natural life. Not once, in any scene of the film, does she stop to consider that she is essentially stealing that other man's body from him, and depriving him of the life he was supposed to have on earth.