It's more or less an advanced personal project to stay on top of the LLM learning curve, rather than just being exposed to news and press releases. I also have an appetite for further wrapping my mind around all of this. I already work in the AI space as web-developer on the B2B & enterprise side of things. My opinion here is that there are going to be loads of use-cases and necessary plugins, which for privacy, legal and security reasons need a proprietary solution and won't be able to interface with any third party APIs, plugins or frameworks.
I think that is a phase, which will come to pass, eventually most of the plugins and apps which are going to be popular, will likely run their own models or use open source models. Because the API calls for complex applications to OpenAI are currently far from economical. In the end you will have to charge the user, and that is going to be the crux. As a sole developer, doing loads of experiments on less than 50 documents, I am already crossing 50$ in API calls within a month. I can already run llama.cpp, but its just not good enough; but the cost would effectively be 0$ (not counting my hardware).