It's hard to make this point without a normative argument, but by analogy to land, a company is not only the land but also the workers laboring on it. It's reminiscent of serfdom. The serfs are attached to the land, and they own very little of it (if at all, and with many strings attached), even though their continued work is a large reason why the land would be considered valuable in the market in the first place.
But this analogy fails, too, because in Silicon Valley, the serfs aren't attached to the land. Generally, someone who's an early employee at a tech startup has the option to go be an early employee at a different tech startup, without too much hardship. They aren't tied to the company the same way a serf is, where uprooting one's life to go work a different stretch of land was absurdly difficult, if not impossible.
