If you look at the map, yes, but the real location of the servers should be noted on a map of network topology to make more sense. If you do, you will see that the server(s) in Miami are actually in a pretty good location for Latin America as most ISPs in Latin America do have links to Miami and the IX there. You will also notice that the server on Fiji is not serving all ISPs there as they are not exchanging traffic locally (but the server really really helps the ones that do peer with it).
As ISPs start to exchange traffic more locally, it makes sense to have more root servers locally, and anyone that want to have a root server closer to them can “just” get an agreement with one of the root server operators that deploy according to Anycast. You can see on https://www.root-servers.org who does.
My goal with doing this map, and explaining a bit of the economics is to try to make people understand that the root servers in the world is not where the problem is regarding DNS operation. It is the fact that some TLD servers are not very stable, exists in few locations, and that the DNS servers for the domain name you are looking for are not configured correctly.