Bitcoin, as he alludes, is really a form of barter and not currency. Unlike currency, it is not very liquid. Having a million dollars in Bitcoin can't be converted in one fell swoop to dollars.
Maybe something didn't click in your head... Bitcoin is a currency. Dollars are just the middlemen here. If you earn Bitcoin and spend Bitcoin, where do dollars enter the picture?
Philosophy: A route of many roads leading from nowhere to nothing. -- Ambrose Bierce