I heard -and I guess this is now technically a rumor - that a lot of predictive AI pulls from Reddit quite extensively, which means every time someone posts a question to ChatGPT Reddit receives like 1,000 data requests, which is a pain to manage. The API pricing is supposed to make that prohibitively expensive.
Which would make sense I guess (I know next to nothing about how ChatGPT actually works) but unless they had a plan for whitelisting certain 3pp users to ensure 'legitimate' API users still have access (ie if the main purpose is accessibility) but there's no indication hey thought about that at all.