> For example, source IPs belonging to a legitimate Italian ISP should not arrive in a Brazilian datacenter.

You sure about that?

If the entire network is healthy. Yes, and maybe by two(?) transatlantic cables is not the efficient way to serve a page. NYC is probably closer to Italy by network topology than is Brazil.

But if CF had a data center in Italy and one in Germany, there are very valid reasons for Italian traffic to end up in Germany. Like a grid failure, flooding. Or fire. So how far you can take this and still meet SLAs is a little tricky.