an LLM is a curiosity without user data, anyone with a big silo of data can put out something years behind frontier and still instantly see huge usage. No one wants to go to AI, they want AI to come to them, unless OpenAI can stake a claim in a super novel way they're the Dropbox.
It's not like someone is going to use insider OpenAI knowledge to build an LLM so advanced you switch email, phone, or ERP providers
If Apple, Google, or MS are integrating LLMs, they can't get away with "you can talk to this website". The intersection of "has the cash to train a LLM" and "LLM is itself the entire offering" is very small