What a dumb reveal. Not Kumoko's origin, but D being a god masquerading as a human all along. Completely unsatisfying. I'd have an easier time accepting the accident propelled her to divinity by falling through a crack in reality. I always assumed Kumoko's personality was from a real eccentric JK, even if she was just a copy. Now she's completely disconnected from anything relatable or human. What purpose does she have? What agency? Any thoughts or motivations can just be pulled out of the author's ass because she has no grounding.
For what it's worth, Kumoko is, in essence, the character that D had been role-playing on Earth. I can understand you finding it 'lame', but to me, the idea of bringing one of my role-playing characters to life is kind of cool.
She has all the grounding she has given herself over the last five years. Her friends and acquaintances, her experiences, her wins and losses. Yes, it's just five years instead of the twenty-one-odd years of memories she has, when including the fake ones that D gave her, but the most recent five are entirely real, and entirely her own. It isn't fair, discounting those.