I would not call it mocking, merely telling us what they really are.
We have demons and devte, the path of the gursikh is neither, it is right in the middle, with no discrimination between 'good' and 'evil', we hve to become nirgun, without paap, without gun - something that is only possible through human birth.
The hindu gods are devte, in jap ji sahib it says that they can't see waheguru. Maya is, by definition, that which makes you forget waheguru, so they are naturally bewitched by her, it is the natural state of things.
Guru Sahib is not saying good things about them, nor is he saying bad things about them. They have their own duties, which is not to bring us naam.