The entire purpose of compensation like this at the highest levels is to ensure that no other possible group could incentivize you to betray in any way the board or shareholders

Think about it like they are paying based on the question of: how much does it cost to keep this person protecting all of our Crown Jewels AND will never support unionization or anything that gives meaningful power to employees?

The bigger the risk to shareholders if something goes wrong with the stock, or if the CEO defected to a competitor, the more pay they offer.