If the user uses CarPlay and the car's HUD supports 2nd video streaming, Apple Maps' directional arrows will already be displayed on the HUD. If I remember correctly, I think this feature has been supported starting from iOS14 or iOS15. CarPlay users, who can see turn-by-turn directions from Apple Maps on the HUD, expect third-party apps to support this feature as well.
When I checked the CarPlay Simulator, "Instrument Cluster Video Stream 2" is only used by Apple Maps among navigation apps. So I checked the documents for the developers and the CarPlay App Programming Guide since 2022-06, the functionality is not described. So I'm pretty sure it's being blocked by some kind of Apple CarPlay policy. Are there any plans to make the “Instrument Cluster Video Stream 2” feature available to third-party app developers?
This is my own answer to this problem. This issue is addressed in CarPlay developer documentation updated in March 2024, revealing plans to offer services in the HUD area to third-party app developers. We hope that app developers can update quickly to provide better information to users.
