According to SEC filings, Elon himself hasn't sold any recently, but he owns 20% of Tesla, worth about $10B today. Even if Tesla drops 10x, he would have $100M worth of shares. Not to mention all his other assets, shares in SpaceX etc. He has more money than he will ever need.
Tesla's market cap is $764.255B. 20% of that is $152.851B.
Sure, he also probably takes a salary for his role at the companies as well. Still, there's a reason he continues to work I'd assume? It might be he truly wants to get electric car on the road, or it could be he wants more money. In both cases you could ask: "Can Tesla survive his inevitable exit?"
So ignoring Elon's motivations here, as maybe he just has fun running Tesla, who knows, still the question is relevant to other investors into the Tesla stock, and for Tesla's employees.