There is a certain logic to the original ideas of effective altruism. If you want to make positive change in the world, you will be more able to do so if you are a powerful person.

The problem is you can essentially use it as a justification for endlessly pursuing your own personal power. After all the more powerful you become, the more good you can do! In fact it makes it easy to justify committing immoral acts in the pursuit of power-- think of it from a utilitarian point of view! I am going to do so much good once I'm rich, that it will far out weight the harm I'm doing now. In other words, an okay idea that is used and abused by the greedy and power hungry to convince themselves they aren't bad people.