The Cambria rules were introduced by "feature porn" companies, as far as I'm aware and are a means for better marketability through cable, VOD and so on, driven by the goal to make those companies more money, not to make porn more acceptable in society. That market expansion theme with porn that isn't as rough as the gonzo-only crew's used to only works with established players who have existing business relationships with companies looking for some "spicy" opportunities which made both parties money in the past, not with fuck-that-whore-until-she-bleeds-out-of-two-holes ventures planning on a much lower scale. The smaller producers probably knew that it wasn't going to happen for them in the bigger leagues and didn't bother to try taming themselves down unnecessarily.