"Don't be evil" is a meaningless phrase, because "evil" is an entirely subjective concept.
Google was born out of NSA and CIA research grants, and they operate under capitalist incentives. Many would say they have never not been evil. But again, it's a matter of perspective.
It's obviously not a phrase any company would ever take seriously since it has no real legal implications, and it's honestly weird how many people seem surprised and offended to find this out. No one is getting fired because Raisin Bran cereal doesn't guarantee a minimum of two scoops of raisins, either.
Isn't doing that in and of itself somewhat evil?