based on the keynote, they say it will be better in "urban jungles". It was part of the Apple Watch Ultra and said it worked better for the Boston (IIRC) Maraton. I would hope for the phone it works better for navagation in Car Play... I dont know how many times my phone things, when driving forward, that im turning down a side road...
That last bit is a software issue. Apple maps is constantly trying to route me to a parallel street for 1 block in a city and it actually thinks I listen to it. Google maps doesn't have either of these behaviors on the same hardware/APIs.
No, a more accurate GPS will not fix Apple's bugs.
