Some quick searching says TSLA is about $1000 and Elon owns 178M Tesla shares. Assuming Elon owns all those shares free and clear, aren't there plenty of inves

Some quick searching says TSLA is about $1000 and Elon owns 178M Tesla shares. Assuming Elon owns all those shares free and clear, aren't there plenty of investment banks that would eagerly loan Elon the $21B if Elon pledges ~63M of those shares as collateral? (I got the 63M number from assuming the lender requires collateral value equal to 3x the loan to protect against price drops.) Then presumably Elon would sell 21M TSLA over the next year or three to pay off the loan and get the other 42M of collateral out of hock, but sell slowly enough not to crash the price of TSLA.