I see more value on the business side than the tech side. Ask the AI to transcribe images, write an email, parse some excel data, create a prototype, etc. Some of which you might have hired a tech resource to write a script for.

On the tech side I see it saving some time with stuff like mock data creation, writing boiler plate, etc. You still have to review it like it's a junior. You still have to think about the requirements and design to provide a detailed understanding to them (AI or junior).

I don't think either of these will provide 90% productivity gains. Maybe 25-50% depending on the job.