Amazon wouldn't be worth less if someone else owned it and he only owns 10% of the company. So all of it.
Elon sold about $23 billion in Tesla stock from April 2022 to December 2022 to buy Twitter and my memory was the stock going from about $400 to $100 that year. Of course there are other factors in the decline but it’s certainly a component of it. Bezos would need to sell almost 10x that much.