@OP
This an unrealistic expectation. Yes, you can download all the photo tiles from Bing or Google and make an entire photorealistic earth that way. In theory it sounds amazingly awesome. In practice not so much... There are a lot of tiles that don't fit with each other in terms of colors (depending of when the associated satellite picture was taken). So you end up with a square of green and a square of orange / brown next to each other, which looks completely disgusting. You can always color correct tiles one by one but imagine the manpower associated with that...
Also not all areas are available in high res. A lot of places (including first world country) are still only available in low res and they would look awful in the sim unless you're flying at very high altitude.
When it comes to a whole world where you can control a soldier, drive any vehicle, including submarines, go to the grocery store or whatever... that's just way too much to ask. ED would need to hire the entire Arma, Grand Theft Auto and Silent Hunter dev teams to make it happen!
Let's be a bit sensible here.