What is this mystical "future AI" that makes every software developer or engineer suddenly obsolete. Maybe creative thought requires a brain and nothing will ever beat human reproduction in producing engineers.
Most developers today use automated builds, packaging, test runners, app genertors and so on.
Automation in software development is already there, it's been present from almost day 0, but it has so far been aimed at assisting humans, not completely replacing them.
Also I dont thin you realize little magic there is in imagination. Computers can dream, thats what it requires to imagine. The rest is just about finding proper context that fits humans needs, but even that is learnable by machines.
So the question you should be asking is what mystical human ability is imagination that it can't be done by machines.
But again even if it was always outside of human abilities it wouldn't require more but less developers over time.