What makes Rust great is that its design drew upon decades of understanding of programming language theory and practice, and the designers took bold decisions based on that understanding to avoid the mistakes of other programming languages.

The problem with async Rust is that the async idiom is new, and its interactions with the rest of the software ecosystem not particularly well understood. This makes async support glaringly different from the rest of the language.

I'm glad the designers seem to be taking a step back and reconsidering how everything fits together.