Earlier quoted context omitted.
You have a choice though. The exercise price + taxes is the price you pay for potential upside. Not willing to take that risk? Just walk away from your options and pay nothing.
If that's the truth and the employee's best guess as to the company's outcomes are that their options will either be worth nothing or the taxes will be too expensive to afford with the cash available to him, the employee should rationally value any option grant at zero. Startups may find it a little hard to recruit employees if everyone starts valuing options at zero. This isn't in anyone's interests.
I'd argue that it's in the employees' best interest to realistically value the equity portion of their compensation package.