So I think it is a perfectly valid question (albeit an uncomfortable one) to ask. There may be valid reasons for the OP to do/stay in the job that we aren't seeing. Or there may not. We won't know if we don't ask, and the OP doesn't have to answer.
It is well within the guidelines of HN, it adds to the discourse, particularly on a topic that is basically about morals/ethics. Just because it is an uncomfortable question, doesn't make it fall within what should be flagged.