They have the brand recognition and consumer goodwill no other brand in AI has, incredibly so with school students, who will soon go into the professional world and bring that goodwill with them.
I think better models are enough to dethrone OpenAI in API, B2C and internal enterprise use cases, but OpenAI has consumer mindshare, and they're going to be the king of chatbots forever. Unless somebody else figures out something which is better by orders of magnitude and that Open AI can't copy quickly, it's going to stay that way.
Apple had the opportunity to do something really great here. With Siri's deep device integration on one hand and Apple's willingness to force 3rd-party devs to do the right thing for users on the other, they could have had a compelling product that nobody else could copy, but it seems like they're not willing to go that route, mostly for privacy, antitrust and internal competency reasons, in that order. Google is on the right track and might get something similar (although not as polished as typical Apple) done, but Android's mindshare among tech-savvy consumers isn't great enough for it to get traction.
