As the title states, setting timeline.rigidbody.isKinematic doesn't seem to do anything. At least, it doesn't set the actual backing UnityEngine.Rigidbody property accordingly.
This seems contrary to the summary tag, which advises, "Use this property instead of Rigidbody.isKinematic, which will be overwritten by the physics timer at runtime."
This tripped me up for a while, so for my own project, I've just made the setter protected for now.
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