Aveirah, I looked up the study. It says straight out that they interviewed non-Orthodox people who attend Orthodox synagogues. It also says that only 41% of respondents classified as Modern Orthodox!
If you look at the splits between what they label as Modern Orthodox or Centrist/Right Orthodox, you’ll see the numbers are just fine. It’s Open Orthodox that has the problems… no surprise there.
You talk about the things it doesn’t ask about. I have children in schools now, and I can tell you that tznius is taught just fine. They are taught that ngiah is forbidden. The school has a dress code. The vast majority of students don’t have relationships with the opposite gender. So I don’t know where you get your ideas from.
Lakewhut: incorrect. In my shul, which is MO, there absolutely is a requirement that women must dress appropriately when coming to shul. The Rav will admit that the requirements are usually the halachic minimum, so that people aren’t driven away from davening, but they are there. We’ve had times where the Rebbetzin went over to someone to ask her to walk out until she changed, or covered up a bit. We’ve had divorced women who no longer wanted to cover their hair who were told that’s not allowed in the shul.
As for mechitzos, you miss the point of them. It’s not to block men from seeing women. It’s to differentiate the sections for men and women. R’ Moshe held it only needed to be 5 feet tall. It’s just to prevent mingling during davening.