I'm honestly not sure that Apple *ever* planned to bring an entire car to market. Remember when all the analysts and spies were saying Apple was going to make a TV, then they made a set top box called the AppleTV instead? I think this situation is really similar. Would it be neat if Apple did, in fact, manufacture a car? Absolutely. I think it would be amazing. But you can count on one hand the number of successful startup auto manufacturers there are in the world, and even they are having a really hard go of it. I'm perfectly happy to be proven wrong, but I just don't envision a world where Apple has entire buildings full of people designing suspension systems, and transmissions, and rear differentials, and doing crash tests.
Apple replacing the role that, say, Johnson Controls sort of occupies now in the automative space (and they do much more than head units, screens, and software) is a more logical target. They have done similar things over and over by studying an existing market, targeting one or two of its top players, and building better but more niche versions of their products. Remember Rio? Remember Pebble? Remember Nokia? Neither does anyone else. Apple learned everything about these companies and out-designed and out-engineered them. They can certainly do the same to the auto divisions at Honeywell, Siemens, Bosch, or Johnson Controls.
Here is my call on all this. Apple will offer a complete replacement for every CAN bus powered part of an automobile—anything that can be controlled by software, which is a lot now—to any auto manufacturer who wants to work with them. They may even partner with a few companies on vehicles that are completely powered by this experience. Volkswagen is likely one of them, as they are in an arms race right now with Tesla and want to replace their entire product line with EVs by 2030 or something. Apple may even develop battery systems since they have a ton of knowledge built around those now, maybe second only to Tesla.
The pitch to car manufacturers is that they no longer have to develop these systems in house anymore, or hope that Johnson Controls or similar has a part they can use off the shelf that will rapidly go out of date. (Have you sat in a car from just 5 years ago without a screen in the center stack? It's weird. This stuff moves *fast* and car companies cannot keep up.) They can concentrate on whatever they're best at, and let Apple turn their cars into giant iPhones with OTA updating, new features via subscription, and on and on. For any car company not planning to or capable of competing with Tesla, Fisker, or Rivian Apple Car would mean the ability to leapfrog back into relevance. To a small extent this can also extend the life of cars, as they can stay current and "on trend" for longer—because all their best features won't, to paraphrase Steve Jobs, be "fixed in plastic" that can't be easily changed when the new hotness gets invented.
Think of Apple Car as an iPhone, and the car makers are wireless networks. Apple likely even thinks of them in the same way: slow, late to innovate, hobbled by old tech and tied up by regulation. Again, I think the whole Apple Car thing was always a play to own an increasingly large chunk of the systems powering cars made by others, and not an attempt to build a car from the ground up. And again, I would be happy to be wrong.