This video is kinda trash. Obviously Bezos can't liquidate all of his assets immediately, but that doesn't make his wealth fake.
He has incredible power and could liquidate billions of dollars a year without devaluing his assets. There are also massive social opportunity costs in the things he does invest in (spaceships, twitter, venture capital). He could invest for a return in food poverty, poverty (through education loans, if necessary), etc.
Video also overlooks the economic liberal perspective on way billionaires are shit. They are a rentier, exploiting their ridiculous market position to levy rents that others cannot.