Of course these preferences are learned. To prove this, all you have to do is look at the images of the great beauties of the past, for example the paintings of Rembrandt and Rubens. This idea that beautiful women must have bodies like twelve year old boys and tits like cantalopes is very new. The fact that Peterson keeps claiming that his prejudices are supported by history, and doesn't even know this historical fact is one more example of his patheticness.