This graph is also showing system-system dependencies as well as system-component dependencies. I'm assuming that the system-system dependencies are ordering re

This graph is also showing system-system dependencies as well as system-component dependencies. I'm assuming that the system-system dependencies are ordering related which implies the dependent systems depend on the results of the previous system either explicitly or more annoyingly implicitly. That's not a bad thing or necessarily avoidable because a lot of things are dependent in games/simulations. If you look at the big graph there are a couple of core systems that must execute first that are probably setting things up for the next tick and then very quickly many fewer dependencies except for core functionality like triggers and pathfinding. One of the nice things about being able to graph this dependency tree at all is that it means execution can be parallelized easily as long as there aren't too many undiscovered implicit dependencies. Similarly components don't depend on one another but many systems depend on components so changing those often isn't free either.