Comment by danelski

In my experience, the congestion data is not the issue: even with the split across Google / TomTom / Here / Apple / some hyperlocal alternatives, everyone seems to have reasonably good idea where the traffic jams are. Having up to date POIs is a different can of worms only solved by Google, not by some clever algo, but through the sheer brand recognition. They're the only ones that have this data fed to them by POI owners.