This just amazes me.
For the longest time there were really only two suppliers of data: Tele Atlas and NAVTEQ. Everything else wasn't worth touching b/c the quality sucked. Then Google collected their own in their little cars and stopped paying suppliers. I'm not sure why Apple didn't have the foresight to understand this was an enormous engineering effort from Google - not only collecting their own data but the whole platform itself.
I worked as a consultant for one of the two major data suppliers for 3 years rebuilding their backend. 400 years sounds like a reasonable swag.