Besides being unable to find the names of nearby stores on the map, I haven’t experienced any of that with Google Maps on iOS. I saved an offline map many years ago and the app automatically uses it if I turn on airplane mode or the internet drops when I’m driving. Navigation still works and I can change destinations while offline. Maybe you drew the short stick on an AB test?
Driving generally works well offline, but biking, walking, and transit don’t. Some random features like search history or shared lists also seem to not work or work badly offline. Maybe you and the parent comment are using it differently?
