Fair enough. In "real-life" terms, being unable to keep it in your pants should be sufficient to keep you off of the earth's greatest superhero team, but as plenty of characters from Guy Gardner to Major Disaster have shown, harassment apparently just doesn't count when the woman in question can lift a Sherman tank. Which you think would actually be more of a deterrent to that kind of thing by itself, but it just goes to show you how the low the standards for respectfulness towards women really are in this setting.
As for Plas, I actually like him as a character, and I figure half the time he's being written as the "harassment = hijinx" douchebag you describe, and the other half he's being shown as a witty trickster who has some serious impulse control issues but who really loves being a hero and makes jokes to hide how scared he is that he doesn't really belong there. I find that second portrayal both more honest and more interesting, but it doesn't hide the fact that many writers consider being sexually inappropriate towards women to be nothing more than slightly humorous, and never acknowledge all the extremely unpleasant assumptions going into that stance. Part of what I like so much about Diana's position here is that she's confident enough to acknowledge that yeah, maybe there is something mildly amusing about it from a certain point of view, but damned if she's going to put up with it.