If I choose to drive on anything except the freeway, I get told the road is closed, drive it anyway (the road is, after all, not closed) and spend the entire journey with a mapless screen. Great 4G+ reception the whole way. Happens all over NSW. Weird.
Apple Maps pre-loads maps every time you get directions, and the latest version also encourages you to pre-load large areas (sydney is about half a gigabyte) even if you have perfect reception. It’s a free service that doesn’t monetise user data or have any ads, so Apple doesn’t really want iPhones hitting their servers continuously.
If you’ve pre-loaded your map, it downloads new data when you charge your phone overnight on wifi and only reaches out to the cloud for traffic data (and even then, it still has “typical” traffic based on time of day/day of the week as part of the offline map).
Sure, Apple Maps doesn’t do off road mapping at all. But CarPlay works with any (good) third party mapping app, including Google Maps and various dedicated off road mapping apps https://www.coffstrails.com/review-of-navigation-apps-for-4wd-adventures/
Your mates just don’t know how to use their phone is all.