Yes, they are. The people who own and run Google and Facebook and Amazon didn't magically get "capital" from nowhere. They used their skills, and turned those skills into huge amounts of money. In other words, they understood what capital they owned, and acted to maximize their return on that capital.
If you insist on refusing to view your own skills as capital, you're just giving up the chance to maximize (or at least improve) your return on that capital.
If you insist on refusing to view your own skills as capital, you're just giving up the chance to maximize (or at least improve) your return on that capital.