Unity started their physics engine as a test of the job system. When they got the latest PhysX drop, and it was slower, they made it into a full team. Unreal had been annoyed with PhysX for a while, and entertained the idea of writing their own, but never actually did it. When Unity engineers told them about the latest PhysX updates, they launched the Chaos project.
NVIDIA's incompetence is what kicked both of them off, basically. Both engines will continue to support PhysX 3.6 for existing customers.
NVIDIA's incompetence is what kicked both of them off, basically. Both engines will continue to support PhysX 3.6 for existing customers.