Apple market cap is 2.3 trillion.

Elon is worth 191 billion.

He couldn't even buy 1% of Apple.

EDIT: To clarify, Elon's net worth is about 8% of Apple's market cap, but to make any sort of move on Apple, he needs cash on hand. This is why he needed financing for the Twitter buyout, despite being worth loads more than that company. Now, assuming Elon decides to liquidate his assets, their market value would plummet. Realistically he's not coming up with more than $100b in cash. At the same time, putting in a buy call on AAPL to the tune of $191b (or whatever amount he scrapes together) would cause a tremendous surge in the value of that stock. There's simply not enough of that stock changing hands that he can pick up that much at the current market price. He'd be sending AAPL to the moon if it wasn't already there.