> This is less common now, but it was huge during earlier development; a lot of the async work only ran on nightly compilers.
How is this a problem? The crate authors targeting nightly features know full well that they are restricting their pool of users, while at the same time driving the testing and design of nightly features forward. If no one is actually using them, then they are unlikely to get quickly stabilized.
> If the Rust team refuses to ship the features in stable releases
Can you show a case of refusal to ship a needed feature?
> Rust developers have little reason not to use the features.
Rust developers of end user applications don't. Crate authors do, if they want to gain wide adoption.