It is not an issue. It is expected.
ChatGPT is a realized product, with its own model, its own internal prompting, and its own non-replicable tools.
The API is a development platform.
You won’t have your own product invoking a special tool injection to then tell people where to vote, for example, but ChatGPT does. You can’t receive custom “tool” output (only functions) and you haven’t written tons of anti-infringement text for the AI, but that’s what DALL-E in ChatGPT does.
Files work differently, vector store search parameters are proprietary, some text and filenames is extracted and placed into the ChatGPT context automatically.
Different input means different output.
You have a chatgpt-4o-latest for experimentation on the API, without tools or other capabilities. You can place all the input context text you can extract from ChatGPT and just place it as fake system message descriptions that cannot be invoked. Then you still don’t know the sampling parameters or what OpenAI does dynamically to the real ChatGPT efficiencies.
This is no concern for those who aren’t trying to copy someone else’s $1B revenue product and offering no value addition.