MATLAB has had this for years. But it costs $1,000 on top of the existing license cost. And it's lumped together with their GPGPU/cluster tools.
The only type of multithreading in Matlab is the type that is built into the core language, and you don't get any control over that.
Finally, the claim to originality here isn't just the introduction of multithreading (which isn't even new in Julia!), but the particular threading model and scheduler, which lends itself particularly well to composable multithreading.