His intentions are obviously evil to anyone paying attention, but saying vaccines would "decrease the world's population by 10-15%" implies getting rid of people who are already alive. Which isn't what he said or was talking about. He was talking about decreasing the growth rate so fewer people would be born over a certain period than otherwise would (e.g. 425M people born instead of 500M). The difference being that one is murder, the other isn't. Both are evil though assuming the method for decreasing the population growth isn't actually a healthier population choosing to have fewer kids as he claims but instead forced sterilization or something similar from vaccines. On the other hand, if his claim (again, being that healthier people choose to have fewer kids, not that vaccines themselves are going to decrease the birthrate) is correct and genuine, which I highly doubt, then there's actually nothing particularly evil or wrong behind what he's saying.