But also no direct copying, typically. Would OP really be happy with an AI that reliably rewords everything so that attribution is not required but still reproduces the information?

Human educational systems penalize you for not citing sources (i.e. not showing your work, not crediting referenced works). Why should an AI system be exempt?

Because it's not a student at school, obviously. You didn't cite the source for the claim you just made there and you didn't need to.