OpenAI spends about $700,000 a day, just to keep ChatGPT going. The cost does not include other AI products like GPT-4 and DALL-E2. Right now, it is pulling through only because of Microsoft's $10 billion funding
LLM's are pricey to train and evaluate, much more so than compositional models.
But no, OpenAI aren't going bust due to this. Given that they have the most successful LLM on the market, it's safe to say that they probably know how much they cost, and can calculate roughly how much their yearly spend will be.