Tonga has the same Starlink coverage as New Zealand, its a global system limited only local approvals to operate and currently local ground stations.  Its does have limitations at higher latitudes but this is being addressed by new orbits (near polar I believe) primarily to serve Alaska initially.

When a full constellation of laser equipped satellites are deployed, it should be possible to reach the likes of Scott Base and even the South Pole station from NZ.  Quite a few intermediate satellites required so will be interesting to see how difficult that will be to coordinate. The same applies to any remote Pacific Island so there is a potential revolution there.