The default limit is fine for most RID_Owners but 3d instances, CanvasItems, and physics bodies need a higher limit.
There is a small memory cost to increasing the limit, so it should only be done where needed.
If the module is enabled (default), 2D physics works as it did before.
If the module is disabled and no other 2D physics server is registered
(via a module or GDExtension), then we fall back to a dummy
implementation which effectively disables 2D physics functionality (and
a warning is printed).
The dummy 2D physics server can also be selected explicitly, in which
case no warning is printed.
