Physics causes balls to move very slowly

In the glTF Sample Viewer the balls roll very slowly down the track in this renderer. However they roll properly in the Babylonjs renderer.

Sample file here:
https://github.com/KhronosGroup/glTF-Sample-Assets/pull/256#issuecomment-4056265752

* https://github.khronos.org/glTF-Sample-Viewer-Release/physics/
* https://eoineoineoin.github.io/glTF_Physics_Babylon/packages/demo/dist/#sceneIndex=0

Start by reproducing the slow ball motion in the linked glTF Sample Viewer physics demo, then compare its behavior with the linked Babylon.js renderer and the referenced sample asset. Trace the physics or renderer path responsible for the differing speed; the issue is done when the balls roll at the expected speed in the Sample Viewer.

Written by the indexing model from the issue text.