To answer your question: Very unlikely. Swift has a lot of irrelevant complexity from its Apple/Objective-C interop, poor reflection support, poor IDEs (Xcode) compared to established platforms such as Java 8 or alternatives such as Kotlin, Scala and so.
I don't know the exact answer, but Swift takes a higher-level task/queue approach to concurrency, letting the OS handle more of the underlying thread management. So if you wanted to write a concurrency stress test you'd probably write it on top of those constructs.[1]
I'm not sure what you mean by "irrelevant complexity". Maybe you could cite some examples. Limited reflection/dynamism was an intentional design choice for greater safety, and there are complaints, but it's not without benefit. And it's a bit hasty to criticize lack of IDE support when it was just open sourced 7 months ago. That's like criticizing Scala for lack of IDE support.. in 2005.
While the constructs are higher level, the compiler still needs to deal with all of this complexity. Normal developers can ignore this. But there will be a memory model and a modern language should specify this. If swift does not have an equivalent idea of what its memory model should be, the ARM/X86 splits will lead to interesting bugs.
