Yes, indeed. The new measurements of IPs served is preparing for building the GeoDNS configuration so that all countries are serviced by a minimum number of servers (20? 30?) and all the servers are (overall) getting a proportional amount of traffic as well as we can figure out.
Indeed. “As close as possible” is more about minimizing the risk of asymmetric routing and dropped packets, not so much for accuracy.
Years ago someone added the first server on some island in the south pacific. It had a round trip latency of more than a second to North America if I remember right, but both the monitoring system and ntpd on a test server found it ridiculously accurate all the same.
In short: I think we can make the computer do it better than how it works out when humans make the choices.
When people choose specific countries, it’s (best case) either a “no-op” because the system by default would have done the same or it’s an attempt at working around the issues you outlined with underserved countries.
In the worst case it’s causing problems when large user populations choose to use servers in Australia or whatever (for example the snapchat incident some years ago). There are a number of other cases where it’s actively working against our attempts at balancing the traffic, which then can exasperate the problem of the underserved countries.
As you point out all this depends on the system doing a better job with the default zones – that’s an obvious prerequisite! My plan is to have a new DNS name for the new zones and then over time migrate the old names to point to the new one (probably country by country so we can start by migrating things that work poorly now).