Apple Maps is not a paid service. It is not supported by ad revenue and data tracking like at Google and other places. As you said, Apple is staying core to who it is. It implemented Maps as a part of their ecosystem, across Siri, Spotlight, Calendar, Contacts, Reminders, Weather, Photos, and Safari. It works seamlessly between Mac, iPhone, iPad, CarPlay, and Apple Watch. My personal data remains private.
So, in what sense did they "miss" Maps? They weren't first to rush to market with a system to collect your data and sell it?
We shall see with AI. From all evidence, it appears as if Apple is taking a similar approach to what they did with maps. They are implementing it as a set of features across their ecosystem. And, in their initial offering, their writing tools (available in every Apple and non-Apple app that uses the textbox APIs) work passably well throughout the system. Are they perfect? No, but I don't have to worry about someone selling my data. Will they get better? Of course.