The basic thing is that the developer had been swatted multiple times right before that video. Swatted by a fan of the YouTubers who made the video that Louis commented on.

But the targeted update thing isn't even possible on GrapheneOS. The update server is basically a basic web server. The updates are stored on the servers and the update client downloads them. All update files follow the same naming system and the update client downloads updates using that system.

The update client never sends any IDs either.

So if GrapheneOS can't get unique IDs, then how can targeting be done? It's just not possible.