Yep, this was my understanding too. It doesn’t change the fact that the area in space and time is now occupied by grabby aliens. The model and diagrams could ea

Yep, this was my understanding too. It doesn’t change the fact that the area in space and time is now occupied by grabby aliens. The model and diagrams could easily be modified to use some heuristic like allowing older civilizations to take over younger ones when they collide, but it wouldn’t really matter for the purposes of the argument.