If you're Jeff Bezos there's no bank that is going to lend you 100B$ against your stock, because:
1. they don't have this money available themselves
2. there's less than 100B$ liquidity to dump these stocks on the market if they go down in value and Jeff's assets have to be liquidated, so the bank will limit the amount of money it will lend
If I own 0.01 percent of any heavily-traded stock, it's 100% liquid. I can sell it whenever I want at a moment's notice. In any such accounting it will be added to my liquid wealth. But if I own 25% of the same stock, it's illiquid.
If I also run the company, then it's worse because any attempt to sell a large part of my holding will itself trigger a crash in the price.
Hey poors, take example from Jeff! He's not liquid at all, like all of you, but he's always so happy!
By now it only feels to me as a cheap way to hijack the discussion and derail it further from the fact that we have to debate why billionaires exist and not how liquid they are.
In the end the anti-billionaire/anti-system sentiment exists for valid reasons and it doesn't need to be educated to show us that there is an ever growing discontent with the way things work.