Joe Armstrong, Erlang, software for a concurrent world. It passes the first criterion: time tested. Not so much the second of having been previously impossible, because Erlang could and does run on yesterday's hardware.
Erlang isn't theoretical. It's practical engineering. It works because message passing is what distributed systems have to do and at scale portions of a distributed system will become unavailable.
There are very specific problems that require more detailed engineering like Lamport Clocks and Raft Consensus Protocol. But not the general case. The general case is "being good enough" as is the nature of engineering.
Erlang isn't theoretical. It's practical engineering. It works because message passing is what distributed systems have to do and at scale portions of a distributed system will become unavailable.
There are very specific problems that require more detailed engineering like Lamport Clocks and Raft Consensus Protocol. But not the general case. The general case is "being good enough" as is the nature of engineering.