Not to mention that in modern times the trends usually change to match our better understanding of the world. Smoking went out of fashion when we learned how unhealthy it is. Tanning is popular in some circles, but I'd argue that it's mostly gone out of popularity as well in large part due to seeing what it did to the skin long term. The super skinny look was briefly popular, but as we learned more about health actual fit and slim bodies became the ideal. And arguably have been for something like 20 to 30 years now.  A whole lot of our subjective preferences are born from seeing the tire fires that result from other paths. The fact that if fat was EVER popular it would have been that distant from now would really say something about how regressive it'd be to fall back into it.