So how is the modern way to work around issues like network partitions, servers not responding, going off and on on network connections, duplicate answers,....?
Futures-oriented programming - helped by the "async" or "generators" support in quite a few modern languages. Wrap timeouts and retries around everything, and process the timeout errors accordingly.
RPC doesn't mean that a remote function call looks exactly like a local one. That was a mistake. Modern RPC systems return composable futures which make it trivial to do timeouts and retries, send off many requests at once and wait for all/some of them to return, and so on and so forth.
If you're doing something that shouldn't happen more than once, generate a transaction ID to identify it by.