Why VertexProxy can't be accessed from object w/ animations?

Why? and is there anyway to access it?

because the mesh positions on a deformed armature would need to be recalculated every frame

reinstancePhysicsMesh()

or something like this updates the mesh position but it’s very expensive to run each frame

When a mesh is parented to an armature this over-rides all vertex modification you might try to do to it. You can’t set the vertex colors or positions and you can’t change the UVs or anything like that.