These particular options have the tax advantage that, for long-term investors, the paper gain on exercise is not recognized until the stock is sold and it is then taxed at long-term capital gain rates.
Although qualifying ISO dispositions can be reported as long-term capital gains on the 1040, the bargain element at exercise is also a preference item for the Alternative Minimum Tax.
Such leaders can be expected to exercise much more international centric decision making and feel much less need to subordinate the long-term interests of the U.S. over those of other countries offering better short-term benefits.