> I think judging him as a evil exploiter with weak ethics is a little harsh.
Why? Doing something bad doesn't become OK just because you got paid a lot of money to do it. Indeed, a reasonable definition of ethical behaviour would be doing the right thing even when faced with significant incentives not to.
I have never been forced to choose between becoming a billionaire and holding onto my ethical convictions, and I suspect you haven't either. I'm not comfortable with either of us standing in judgment of someone who has.
I've also never been faced with the decision to torture someone or not, that doesn't stop me from making moral judgement about those actions either. The point of an ethical system is to help you make judgements about decisions, if your answer to every ethical question is, "I've never had to make that decision" your ethical system is useless.
There's a difference between saying "what John did is wrong" and "John is a bad person." I think the OP was saying we should be cautious in making judgments of the second sort.
I'm perfectly comfortable condemning someone who acts against the ethical principles I and many others believe in, however much they were paid to do so. That's why they're called "principles". It doesn't matter whether it's a schoolboy violating them for a chocolate bar or a multi-gazillionaire CEO doing it for his bonus.
This kind of attitude inevitably leads someone to cynicism and misanthropy: the Milgram experiment suggests that nearly every human being is worthy of moral condemnation under your reasoning, or would be if given nothing more than explicit instructions from an obvious authority figure to do something wrong.