I don’t think sarcasm counts! And the confusing thing about English is that sometimes a double negative is used to intensify the negative, especially in colloquial speech or dialect. Tone and emphasis can make a lot of difference. I do pity poor foreigners who have to learn English!
Not a bad idea. He could use it to train himself as a cleaner, with advice from Flo, and practice by volunteering to clean for the old people. He’d build a reputation, get recommendations, and gradually be able to make money at it. If he wasn’t Jack.
I think it’s a pretty good joke, but I may be dad-adjacent.