If anything, a high base pay would be a dis-incentive to perform well, because increased wealth (a) reduces the marginal utility of additional compensation, and (b) makes the CEO less vulnerable to going down with the ship. The same goes for "golden parachutes".

IMO, if incentivizing good performance was really the goal, then companies would hire CEOs who are not already wealthy, pay them only enough base salary that they accept the job and can focus on it without worrying about paying bills, and compensate them mainly using illiquid, very long-dated stock options, which become worth a fortune if and only if the company is still around and profitable far into the future. It turns out that this is basically how founders are compensated, and it's a wonder that shareholders allow public-traded companies to be run in any other way.