I still think this is one area Rust missed the mark. Go concurrency is quite amazing. Its fast and easy to reason about. Every language can learn something by how goroutines work here. Most importantly, it feels like you're just interacting with synchronous code. There is no "what color is your function?"[0] problem.

The fundamental primitives Rust decided to adopt are just not ergonomic by comparison, and suffers from the aforementioned "What Color Is Your Function?" problem.

An otherwise great language decided to adopt an old hand grenade in regards to async primitives

[0]: https://journal.stuffwithstuff.com/2015/02/01/what-color-is-...