Are "hoax articles" academic misconduct? They stretch the ethical considerations, by roping in reviewers and editors to participate in research (with real time and energy) without informing them they are participants, extracting permission, or informing them of risks.
I never used to say no to reviewing. These days, I say no a lot more. If it's grant deadline time, I say no. If it's a paper whose subject I'm not completely comfortable with, I say no.