Deep in the iOS16 release notes there is a little asterisk that states Apple Vehicle announcements coming in late 2023<p>https://www.apple.com/ios/ios-16-preview/features/
It doesn't say "Apple Vehicle" it just says vehicle, capitalized as the first word in the sentence. In the context of Apple CarPlay, the section that it's in, I think it's a more reasonable assumption that they will announce which vehicles from companies that actually make cars will come with the new CarPlay.