Getting back on track, the lack of cultural unity was not in fact generally a problem a few decades ago, before the internet. Each community could have its own standards and this wouldn't pose too much of an issue, and this is more or less the way things worked. This system dissolved long before television, which was heavily regulated (hell, they weren't allowed to show belly buttons), became able to seriously impact standards of provocative clothing.

I think you are overestimating pre-internet uniformity here. If for example one spent time in Crown Heights one would have Orthodox Jews, generic African-Americans (mainly Christian), and some Muslim African-Americans. Each group has different ideas of what would constitute provocative clothing. Or to use a different example: when I was an undergrad I was involved in an interfaith Jewish-Muslim group. One thing that struck me was that among many of the Orthodox Jews, women wearing pants was considered what you would probably call provocative, but hair covering wasn't an issue. In contrast, for many of the Muslim women, the reverse held (pants fine, uncovered hair immodest).