As a related point of consideration, from a package health POV, swift-numerics does not seem to be maintained well. The last tagged release was 1.0.2, released on November 18th, 2021.
swift-async-algorithms has also been frequently criticized by the community as not evolving fast enough (I personally hold this view more for swift-numerics rather than swift-async-algorithms).
All of this is to say that even though part of the rationale as I understand it for keeping these packages out of the Swift core library was so that they could move faster, they do not seem to be doing so.
I definitely think these libraries need active maintenance to be considered as stable even for those consuming it as a SwiftPM package, let alone the Swift standard library.
