Which the AI will just make a stab at without digging in and asking clarifying questions or examining all aspects of the codebase to spot what challenges there are with doing it that way with the specific custom business logic needs needed for the rest of the application, and then get it very wrong and not anywhere close to what was intended (although possibly exactly what was actually asked for).

Meanwhile even a slightly seasoned developer will know to ask for clarifying questions on various aspects of it, or point out challenges with the existing codebase to match the requested requirements (sometimes after taking a stab at it themselves and realizing it doesn't work).

There are ways to prompt the AI to produce better results, with very specific and detailed requirements that include tricky aspects of the technology (that developers are aware of and can provide when they write prompts), but the typical requirements that come down from management ain't anywhere near that.

Not saying AI won't ever get to that point, but we're not there yet.