I think, most likely, you'll still need developers in the mix to make sure the development is going right. You can't just have only business people, because they have no way to gauge if the AI is making the right decisions in regards to technical requirements. So even if the AI DOES get as good as you're saying, they wouldn't know that without developers.
It’s short term thinking IMO, but it’s my interpretation of the argument AI proponents are making.
For some definition of work, yes, not every definition. Their product is not without flaw, leaving room at for improvement, and room for improvement by more than only other AI.
> There are no vulnerabilities
That's just not true. There's loads of vulnerabilities, just as there's plenty of vulnerabilities in human written code. Try it, point an AI looking for vulns at the output of an AI that's been through the highest intensity and scrutiny workflow, even code that has already been AI reviewed for vulnerabilities.