If I'm being generous, I think the point the author was trying to make with that introduction is that the concept of property as a social construct is an extens

If I'm being generous, I think the point the author was trying to make with that introduction is that the concept of property as a social construct is an extension of animals protecting physical objects such as food, different than the concept of owning an intangible work. If he was as smart as he clearly thinks he is, he'd realize that once you introduce the idea of owning things beyond objects you can physically defend 100% of the time (something the vast majority of people support), whether or not it's actually a physical object becomes much less important compared to the fundamental idea of socially protected ownership.