Exactly. Apple can register Apple because they don't sell apples so it's not misleading. OpenAI can't register OpenAI because they make ai but it's not open. They could call themselves Peaches, OpenWombat or ClosedAI and there wouldn't be any issues because those wouldn't be misleading.

Do they have a trademark on the word apple with no other context? I thought it was Apple computer, which is distinct.

It's like you are starting to get it.