Because world partitioning is all about streaming levels in and out and thus streaming is spawning and despawning objects et cetera, thus that would trigger garbage collection. I know that’s not an issue but imagine you’re driving a car or character’s moving really fast and thus you’re triggering world partitioned to spawn and despawn items a lot and thus within that cause a lag spike in garbage collection.
Am I correct in this thinking or am I missing something?
While there’s way more nuance to this, here are a few straightforward answers:
world partition cells are quite big by default, so it’s not expected to be constantly loading/unloading cells
if your game’s scale doesn’t fit the world partition settings and causes it to break this ^ expectation, you’re expected to modify the settings accordingly (for example, by increasing the cell size)
the cost of loading/unloading cells depends on what’s in the cells, so if your cells are very dense it will have a higher cost, and vice-versa; but this would apply to any kind of streaming, you’re always expected to not overcrowd the scene with actors because (at some point) the performance impact will be noticeable
In short, the systems are designed and implemented to handle “reasonable” or “average” use very well, and they can be customized to some degree, but if your game differs significantly from the norm you need to be careful.