Maybe it's naive of me, but I would assume it won't take 6 years for Apple to redo the work that Google is ahead on. For one thing, they now know a specific feature to work toward, which cuts some time out. Then, they can likely throw more cycles at this problem than Google could 6 years ago, again reducing Google's lead. Lastly, they probably have a lot of stored raw data (satellite images specifically) that Google didn't have at the start and took time to collect multiple angles over time.