But in this future you described where we can magically one shot stuff, why would anyone use services from businesses and keep paying them? Why not just zero shot it with LLM and keep your money?

Businesses will not keep building if they don't have users, so why would they?

I think you are criminally underrating what goes in a business other than just product or tech. It is extremely hard to write or create a company that makes actual revenue, code/product is maybe 20% of it. Maybe you can say okay so AI will do the remaining 80% of it as well since its so smart. And it might but its even more of a long shot imo.