And those products are intellectual property. The laboratories, prototypes, documentation, data, and parents are all proprietary and belong to the company, not the individual. All the individual can take with him is his experience and a sense of which direction he could pursue in the future.

That's not nothing, of course. But real products require all of the above in order to proceed to market, and all of the above takes a fairly long time for a company to build up, regardless of the experience of the people it hires, because the most those people can do is reduplicate their efforts without the mistakes, and even then pure reduplication is illegal because of parents etc.