The problem is, most young people in the US don't own any land and can't afford to buy any. So they will always need food and rent. So once everything has been automated the only job left is sharecropper.
Of course they can reason. They wouldn't be able to write code otherwise, and I've had Gemini write some very sophisticated scripts. I think you just haven't been using them or else you wouldn't question it.
If they left the deal in place Iran would be free to continue their nuclear program in a few years. This way they have to start from scratch. Also they would have tried to continue pursuing nukes on the down-low this whole time.