To my mind an "x product" is rarely the framing that will lead to value being added for customers. E.g. a web3 product, an observability product, a machine vision product, an AI product.
Like all decent startup ideas the obviously crucial thing is to start with a real user need rather than wanting to use an emerging technology and fit it to a problem. Developing a UI for a technology where expectations are inflated is not going to result in a user need being met. Instead, the best startups will naturally start by solving a real problem.
Not to hate on LLMs, since they are neat, but I think most people I know offline hate interacting with chat bots as products. This is regardless of quality, bots are rarely as good as speaking with a real human being. For instance, I recently moved house and had to interact with customer support bots for energy / water utilities and an ISP, and they were universally terrible. So starting with "gpt is cool" and building a customized chatbot is to my mind not going to solve a real user need or result in a sustainable business.