well it's extremely unlikely to go to zero, and it can just as likely if not more so go up. He's almost certainly going to be offloading the stock at a pre-agreed rate, the kind of rate that means him and his children and grandchildren will never want for anything in their lives. It also exists as an asset, meaning he can borrow against it if for whatever bizzare reason he needs more.
just like everyone with net worths over something like 10 million. Like I say, almost nobody has cash/fully liquid assets in those amounts. Doesn't stop them from commanding vast amounts of resources on lavish lifstyles, not to mention foolhardy projects and follies on the regular.
They’re not options, they’re grants of stock units which vest over time. A unit of stock is a share granted and vesting at its full price, not an option to buy stock at some price later.
While startups use options, most large public tech companies typically do not.