I just completed reading the proposals, watching the talks, and reading the book (Modern Swift Concurrency) and this feature has less than 2 months old. The concept and implementations has been around for a bit.
But what does it really do?
It helps to reason what code you are writting, forget about where is been executed, and helps avoid data races.
Thread Safe code is the one you can call from other threads without having to worry about two functions invoking that memory location at the same time.
We no longer have to rely on the hope and pray method of the Third-party SDKs documentation for this vital piece of information and the develoepers spending days if no weeks debugging the init method of the SDK.
”..not to worry about where is been executed?”
You must read/watch:
Introducing Swift Distributed Actors
Konrad releasing Swift Distributed Actors
Tim Condon using Distributed Tracing in production with Swift
NOTE: All these readings, side projects, and continuous training is part of my ongoing learning of server-side swift development.