Arguably, most of the examples on this page aren't actually evil because of their ambitions, but mostly because they place their ambitions ahead of their morality, or ahead of their loved ones, or ahead of the lives of other people. They might be willing to sacrifice innocent lives for the sake of their ambition, making ambition itself not necessarily evil, but the person who places it ahead of all moral concerns. Vilifying a character for being ambitious in of itself, while it does happen, is rare. But the implication is always that one cannot rise in the world without sacrificing something.
Much of this trope may have stem from the fact that many older societies were so strictly hierarchical that the very notion of social mobility would be a bizarre and even frightening concept to them. And in some of modern ones, to varying degrees, it still is. It was the prevailing morality of these societies (both religious and secular) that a person's lot in life was what they were born into, no if, ands, or buts about it — a peasant was supposed to stay a peasant, a priest was supposed to stay a priest, and a king was supposed to stay a king, etc. Anyone who rises above their station, especially if it was done actively, was viewed with extreme mistrust at best. This is also a big reason why merchants were unpopular in those days — they were often able to achieve wealth comparable to a noble without actually being born into the nobility.
As these societies evolved, each new versions of the ruling class zealously guarded its interests against the new lower classes. Either through propaganda or force. And even in cultures where rising above your rank isn't as stigmatized, the notion you can't do so without becoming an evil (or at least an amoral) person is still prevalent, and openly expressing a desire to achieve fame, wealth, etc. is often frowned upon.
