Prior to the industrial revolution, most private property was land and slaves (or serfs, same thing). Land supports only so many people, and land is finite, so both of those have limits on growth. And tools for any given trade were generally cheap enough that anyone of that trade would own their own set.
With the industrial revolution, suddenly the best ways to produce certain goods were wildly more expensive than what any given worker can afford, and even more wildly more productive. So there needed to be a mode of organization besides "every worker owns their own set of tools," and at the same time, factories were the first thing ever to be more valuable than owning land. So that's why "who owns private property" suddenly became an important question about 200 years ago, when "who owns land" would've been the entire discussion for most of human history.