Just musing
Joker would've put Selina in the Wonder Woman outfit. From his point of view, it would suit her--she is more heroic than villainous. It was probably popular: powerful woman controlling you, powerful woman at your mercy, powerful woman in your cosplay fantasy. Of course, there's all the bondage themes that go with Wonder Woman, including the one where if she's bound by a man, she loses her powers.
Or maybe Joker is a secret Bat/Diana fan. In one stroke, he's set up a Diana as damsel in distress act. It could allude to no-men-allowed virginal and pure Diana, spirit of a purer America. Or Miller knew about Supes/Diana already, and having Bruce rescue Wonder Woman the Whore sets up a triangle/threesome thing.