The point is not that particular feature. It's how this new feature interacts with a bunch of existing language features.
Actually JS just cloned those ideas from C# and Python.
Re:A final proposal for Rust await syntax
by steveklabnik on Tuesday May 07, 2019 @02:07AM
(#19846998)
... and when you get down into the details, there are significant differences in what Rust is doing as opposed to these languages, even if the high level idea is roughly the same.
In a few cases having to do with lifetime management and the borrow checker, that's certainly true.
But the example at hand is fundamentally just cloning ideas from Javascript.