Some people may not enjoy the "making the world an objectively worse place" part. Not everyone is moved only by a fat paycheck and working on interesting problems. Otherwise we might as well assume it is perfectly fine to work on a poison gas that only works on ethnicity X -- after all the pay might be pretty good, and it's a cutting-edge, advanced biochemical problem.

Obviously not saying FAANGs are quite that bad, but still, this is a pretty shallow reason to work somewhere.