Your failure here is that you are using normal math, not Effective Altriusm math. That number should not only include past/current 25 year olds, but also all po

Your failure here is that you are using normal math, not Effective Altriusm math. That number should not only include past/current 25 year olds, but also all possible future 25 year olds, including all 25 year olds simulatable by a future powerful AI. In that context, the estimation is quite modest.