Of course, OpenAI saves the data regardless, but they say they don't use API requests for training data and they claim it's deleted after 30 days.
Shopify (who recently laid me off but I still speak highly of) locked down the public access to ChatGPT's website. But you could use Shopify's internal tool (built using https://github.com/mckaywrigley/chatbot-ui) to access the APIs, with access to GPT4. And it was great!
So look at this from OpenAI's perspective. They could put up a big banner saying "Hey everyone, we use everything you tell ChatGPT to train it to be smarter. Please don't tell it anything confidential!". And then also say "By the way, we have private API access that doesn't use anything you say as training inputs- maybe your company would prefer that?"
The louder they shout those two things, the more businesses will line up to pay them.
And the reason they can do this: they've built a brilliant product that everyone wants to use, everyone is going to use.
Plug in your API key and start chatting. Chats are stored in your browser. You can also run it locally, if you wish. https://github.com/mckaywrigley/chatbot-ui