You are not generating a real physical ID but a representation of an ID, a jpeg. Nor would you be using that representation of an ID to identify and actual person for something that legally requires proof of ID like purchasing alcohol, opening a bank account or driving a car. The sole context for this representation is for a fake persona that exists solely on a social media service.
While it is true that using a fake ID to commit other crimes is generally more serious and is the more common case, producing an image of a fake ID is still recognized as a felony.