Sure, you could implement your own sleep functionality that way and it would be independent of the async runtime but the async runtimes already provide that out of the box in a way that doesn't require spawning a new thread so that is typically what gets used.
Yeah, I get the ergonomic benefits. Same imports you already have, fewer arguments, etc - there are a lot of reasons why people would prefer the specific versions.
It's more that a shared API keeps getting presented as an impossibility without stdlib support, and I don't see why that would be true. Stdlib isn't special like that, nor should it be, and nothing seems to be asking for compiler magic (necessary for await in the first place, but not really beyond that).
If anything, the failure of the ecosystem to settle on a shared API seems to imply there should not be a stdlib version - let the competition continue, don't choose any until it's clearly the best choice forever.
