Rabbonim dress in a different way than everyone else to distinguish themselves. They dress distinguished.
But, we certainly agree that we should not all be dressing like rabbonnim.
IBM executives might wear suits, I don’t know. If they do, it is probably only when they are meeting people. If they do, it is because people expect executives to look conservative also, and so expect to see them in suits.
But enough of me explaining things. If you think you understand why some men don’t wear jeans, you should explain it.