What's the authoritative source for this data?
If it is successfully open source, there could be multiple organizations/groups that are maintaining traffic pools. For example, there isn't huge benefit to pooling traffic data between Australia and North America. Perhaps it would be convenient, but that's about it.
That said, I'm not sure whether it's easier to have a big database or a separated one.
With separation, many people could host parts of the traffic data. As a student I could even host something without getting huge costs.
Without separation, you don't have the complexity of splitting per location.
With separation, databases can be smaller and you can put a database with only what you need in that region. You don't want to have requests from Australia being answered (load balanced) to a European server anyway, so if you host Australia's part in Australia you'll have lower latency and a less complex database.
Without separation, you don't have to keep multiple separate databases. It's a simpler, more unified design.
I don't know which is better.
I'll show myself out