[PotatoEngineer]

It probably has to do with Alternative Minimum Tax (AMT), which is calculated under different rules. It hit some of the Silicon Valley millionaires hard when they exercised their options before the dot-com bust, then held onto the shares for a year to get the lower capital-gains rate, and then the bottom dropped out of the market. Under AMT, those stocks represent millions in income even if they're now worthless.