sometimes, that results in things like the sydney harbour bridge being rendered as a featureless rectangle.
Google does the same thing. You used to be able to use SketchUp to model buildings for them, but, a few years ago, they switched to computer generated models. It was very obvious from the pointy trees and rough edges on buildings.
As far as I can tell, Google isn't doing that. They only have 3D buildings where there are aerial photos that can see the walls of the building, they then use that data to construct a 3D model.
Look at 41 central park west train wreck. You have >20 good photos to work with, but the end result doesnt even maintain straight windows. Balconies look like Lara Croft breast from first Tomb Raider, not to mention they are all different geometry despite high quality source material showing them being all the same shape. The best data saving option would probably be no additional geometry at all, just a texture.
99% of the time it works great because you don't really care if a virtual house exactly matches the real house. You just want to see some realistic looking housing estates.
However the downside is when you go and see some well known landmark. They didn't write a procedural palace generation routine so when the AI sees Buckingham Palace it has to pick the closes "normal" building which is apparently an office block.
I suspect the best way to fix that would be to detect when the AI fails and fall back to Google Maps style scanning, which looks worse, but actually matches reality. You could also do landmark detection fairly easily - Bing Maps must have enough data about what people search for and take photos of.
There are 341, but note that London UK is not one of them. Many are in the USA.