There's nothing unique about London cabbies, in that regard. All over the world there are drivers who are familiar with the road system they live/work in.
Amused how you managed to find a way to imply that, as someone who spells utilization that way, his opinion is somehow inferior to a natives! (You might, given this attitude - to say nothing of your username - like "the book of Dave", by Will Self, which imagines a future society which has at its scripture a notebook from a 20th century London cab driver!).
Historical data? Sorry - I just want to get across town. I need to know how to get there, avoiding any local, current problem. Google does that - or have you not checked? State of the roads? My car's got suspension, so that's not really a problem. Also, you're out of scope now; the knowledge doesn't cover that, and I'm not always going to be driving myself; I might chose a minicab from someone more sensibly priced, friendlier (rather an Asian with something to say, that an outsized racist who's afraid to cross Battersea Bridge) who also has access to Google Maps, and a radio network of colleagues.
Face it, London Cabbies are going to go away. Might as well deal with in instead of clinging to increasingly desperate USPs!