I think a lot of the original temporal/cadence authors were motivated by working on event-driven systems with retries. They exhibited complex failure scenarios that they could not reasonably account for without slapping on more supervisor systems. Durable executions allow you to have a consistent viewpoint to think about failures.

I agree determinism/idempotency and the complexities of these systems are a tough pill to swallow. Certainly need to be suited to the task.