Thank you for reporting a bug to Unity.
After reviewing the behavior, we've confirmed it aligns with the current design and intended use of the feature. We understand this may differ from your expectations or workflow.
We will close this case as 'As Designed.' If you have feedback on how the feature could better meet your needs, please let us know - we value your input and consider it in future improvements.
additional info:
Based on the provided reproduction case, one thing that needs to be understood for rigidbody x rigidbody pairs is that either pair.colliderEntityId or pair.otherColliderEntityId can be the collider you are using to filter with.
if(pair.colliderEntityId == m_TrackedColId || pair.otherColliderEntityId == m_TrackedColId)
{
//either of the ids is the tracked id, execute whatever modification is required.
}
Cheers,
AlexRvn.