I thought this comment chain was about durable execution in general. Temporal seems to be that plus some RPC stuff that is a lot more than "nothing special."
All the durable execution systems have to run your code in certain way that persists steps like RPCs (and need to provide a mechanism for you to tell the system which functions have RPCs) so they can recover in case of process failures. They all also happen to provide common orchestrator features like retries and timeouts because devs find it useful.