While ‘local tastes in women’ may be one factor in the use of local models, I think that local laws, culture and other restrictions could easily make it a necessity for certain countries. For example, Japan is famous for having its own quirks and preferences is sexual “turn-ons” and the availability of images of violence and sex. Its famous manga and hentai comic books are fairly widely known, and though I don’t have any firsthand experience of Japanese pornography, it seems plausible to me that the same the same outllook carries over to phographic images.
However, though many of us might be shocked by many popular syles of Jaapnese sexual imagery, and how readily available they are, even to children, Japan also has tight strictures on what can be pictured. Many of the “bread and butter” images of some American pornographic magazines might not be allowed. (Oddly, this owes more to American prudery than Japanese: many of those laws were imposed by the US occupation Forces after WWII)
Shaving (or lack thereof) of pubic hair is one area where local legal and cultural standards are particularly likely to differ between nations. I don’t know a great deal about American pornography, but it’s my understanding that most popular US magazines, including Playboy, refuse to allow untrimmed “natural” pubic hair in theirUS photo layouts – yet pubic hair is, by its nature, a secondary sexual characteristic, just as breasts are. Undoubtedly, other nations view it differently. In some countries, complete shaving would seem “too slutty” or “unnatural”.
When I was growing up, my tastes agreed full with Playboy’s. I too didn’t like to see (pardon me) “full bush” or luxuriant armpit hair, though I was not at all aware of how those preferences were molded. A friend recently showed me a selection of playboy centerfolds from the 60s/70s. The models were often sufficiently heavier and rounder that I believe Playboy would refuse them outright today. Even the hairstyles -attractive at the time- seem distracting and even ludicrous today.
It would be easier to fall afoul of cultural preferences than you might think. In parts of India, touching something with your feet is considered an act of disrespect, and I’ve known Hindu families that go the Hindu equivalent of “blessing themselves” if their bare feet should happen to touch a book when they’re at home. I wouldn’t expect an American photographer doing a layout on "Women in Law School’ to know or fully understand that.
Of course, India has become far more westernized since I knew those families, but still wouldn’t want to guess how various sectors of Indian society would draw the line on leather, for example. Would a leather riding crop in certain settings cross from prop to disgusting violation? Better let an Indian editor decide.
Playboy strives to be fairly “mainstream” within the market. If anything it has always erred to the side of conservatism. As a curious teen, I found it unoffensive, which was a real plus. I had friends who favored “less classy” magazines I found disgusting. No one wants to purchase pornography that they find, for whatever parochial reason, more off-putting than arousing.