As soon as you get the power your competence does not matter. The same thing happens with politicians. I would not let Obama to mow my lawn, nevertheless he is the president of the most powerful country. On this background Jamie Dimon is OK.
I guess nobody gave you the memo. Politics and being on a board of a publicly held company is just a way to legally steel in the name of "Performance Based Pay"! It is a great system where you determine your own compensation and everything is decided among friends. If anything goes wrong you just hang the little guy that is working his ass off for you while you play golf. The corporate ladder BS is a excellent carrot to dangle over your worker ants to keep them motivated. I just wish I could do that!