This has a map of the Wikipedia colocation sites: https://wikitech.wikimedia.org/wiki/Clusters

I'm wondering a bit about your new zealand redirect, as there is no colocation site in new zealand on that map at least.

This isn't going through the Wikimedia CDN network. It's on wikimedia cloud services, which is a free computing infrastructure (OpenStack/K8s) for community members to build community maintained tooling for Wikimedia.

Still think this is a nice idea in theory. In practice I often vendor stuff like this, meaning I just don't use CDNs and deploy "local" copies. I could write a few pages about why this is a bad idea, but there are also some advantages.