Bookworm, you're right, but it's in such common use as to be unstoppable.
If "human error" just means "error", then I don't think it's unreasonable to talk about subcategories of error. "Pilot error", "maintenance error", "ATC error" can all be useful terms if taken in context and with perspective. I share your concern that the term has been used in the past as an excuse for failures of the broader system, but that doesn't mean that we can't talk about such failures to perform to the expected standard.