I am no friend of Satanic Arabia, but revoking sovereign immunity for the fraudi potentates would open a huge can of diplomatic worms.
With that precedent, lefty activists would flock to the courts to sue every non-communist government in the world. They would eventually find pliable judges who would order politically motivated asset seizures, arrests, and similar outrages. These would be overturned but in the meantime, there would be chaos on an unimaginable scale and the disappearance of all foreign trade and bi-lateral cooperation of any kind.