It's literally true that Rust tried and failed in the sense that Rust's early design was extremely similar to Swift's, polymorphic compilation and all, and it was thrown out when it didn't seem to work. Swift pushed on it harder, and got it to work.
But it's less so true in the sense that the two teams had different use cases, and simply took divergent paths. Rust took the "easier"* path that limited expressivity in favour of a simple execution model that requires a minimal runtime, which in turn enabled them to focus on more interesting static analyses. Swift took the other path.
* This may sound like a slight against Rust, but both the Swift and Rust folks who worked on this stuff agree that what Swift did is a comically huge amount of work in pursuit of a relatively niche use case (idiomatic-feeling system apis). There's only so much time in the world, and Rust spent its time on other problems.
But it's less so true in the sense that the two teams had different use cases, and simply took divergent paths. Rust took the "easier"* path that limited expressivity in favour of a simple execution model that requires a minimal runtime, which in turn enabled them to focus on more interesting static analyses. Swift took the other path.
* This may sound like a slight against Rust, but both the Swift and Rust folks who worked on this stuff agree that what Swift did is a comically huge amount of work in pursuit of a relatively niche use case (idiomatic-feeling system apis). There's only so much time in the world, and Rust spent its time on other problems.