I've wondered about this. Apparently there's an API that an EV's iPhone app can use to provide such information to Apple Maps. https://support.apple.com/guide/iphone/set-up-electric-vehicle-routing-iphc5e3a4b4b/ios
Would it be as good as the routing my Tesla's built-in nav gives? I don't know, it would depend on the details that the app provides to Maps, and Maps' interpretation of that data. I haven't heard *anything* about Maps' EV support since it debuted.
The link you sent discusses planning a route from one charge station to the next.
I can do that right now with Apple or Google Maps, but I don't think there is a snowball's chance in Hell Apple Maps will ever pilot a Tesla.
I mean, if it cannot hook into my system and tell me how many miles I have left until I hit a supercharger, it's useless.
Also--I have full self driving (and beta 10) and driving directions relies on the Tesla Sat Nav--you can't use Autopilot with freaking Apple Maps--the car won't know where to go because it uses its own system.