If the world is 2PB of data then Europe alone would be about 200-300TB of data. You need a lot of harddrives to store that. X-plane doesn’t have ortho out of the box, that’s why you have to download ortho tiles manually and that’s without AI generated buildings.
This sim is an online platform and that makes it what it is. You can cache parts of the world if you want but takes a lot of disk space.