Unexpected productivity boost of Rust

The Rust example that you point out might not trigger compile time warnings in other languages, but most OS mutexes (certainly the ones in Windows and Linux) will complain if you release them on a different thread than you acquired them.

You've misunderstood somehow. The point is that Rust detects the mistake at compile time so you don't get to those runtime errors (which might be very rare or context-dependent).