There's a blurb in the article:

>"Massgrave, the group behind Microsoft Activation Scripts, has noted that Windows setup sends hardware info to Microsoft and receives identifiers back that are later used for Store access and licensing. Blocking GDID assignment breaks both activation and UWP apps."

I think probably it sends the gdid back to Microsoft as part of telemetry/updates/MS account periodic re-auth, which lets them know the current IP address, and then once the government has Microsoft's logs and the various target websites' logs, they can correlate based on IP address. I don't think it's actually sending the gdid to the web sites. Maybe.

This serves to further illustrate that nobody should be using Windows for anything that involves the need for privacy. And doubly, triply, and morefold so, nobody should ever sign a Windows machine into a MS account for any reason.