That’s not quite true. Take a look at all the billionaires destroying society. Being evil is the surest way to get to get rich. In fact it’s the only way to amass that level of capital: there’s no ethical billionaire.
This feels like a wild overgeneralization. People can become rich without resorting to evil methods, especially now with global markets and software. Case in point: Minecraft was wildly successful, and now Notch is a billionaire.
Pre-wealth, Notch was friendly, kind, and downright jolly! Even as he started to accumulate wealth, he was donating huge sums of money to various indie games. Whenever a Humble Bundle dropped he would top the leaderboard for the amount he paid for the games. Things took a major turn for the worse after the acquisition and after he left Mojang. That's when he ran out of purpose and turned to drugs and conspiracy theories.