My pet theory is that OpenAI are cooking high quality user data by empowering GPT with all these toys + human-in-the-loop. The purpose is to use this data as a sort of continual evaluation sifting for weak points and enhancing their fine-tuning datasets.
Every human response can carry positive or negative connotation. The model can use that as a reward signal. They claimed to have 100M users, times let's say 10K tokens per month makes 1T synthetic tokens. In a whole year they generate about as much text as the original dataset, 13T. And we know that LLMs can benefit a lot from synthetic data when it is filtered/engineered for quality.
So I think OpenAI's moat is the data they generate.