If someone is using a wish spell to make a better map, do you really think they'd just proceed to make that map freely available to everyone?

Also, even our maps have issues. Like projecting a sphere's surface onto a 2d image, you end up with scaling issues that make Greenland look as big as South America. You can't take a string representing 100 km or something and accurately determine the distance between points in any global map. Some do it better than others (like the projection that tries to peel the earth like an orange and then flatten that peel in 2d), but even they lose some accuracy (you can only measure accurately if you don't need to cross a tear in the "peel").