I’m sure domain specific tuned models will be developed, medical fields are building this kind of thing, and I’m sure that the financial sectors are also looking into it, but the issue I can see is that an AI that makes money for you is a very valuable asset that people will not be making public.
Training an AI to per very good in a specific field will take either a lot of people working for free with public information (Open Source) or institutions building models internally with private data and possibly offering access for a fee.
The GPT models are primarily general purpose AI’s, you could perhaps build up a set of prompts and methods that centre the AI’s attention, but it is certainly not a small project.