Regarding the "weeding out"/leniency with male models:
I'd argue you could have the same logic regarding female models, too. Without having this post moderated, most of the tall (5'9+) girls I know in real life do not have the right bodies to model. And while you'll always have girls willing to work hard to achieve that body, then the issue of photogenic and facial symmetry come into play. I think you'll quicker find a 5'7 girl with perfect bone structure and 35" hips getting scouted before a 5'10 girl with 40" hips and a poor bone structure.