Opening this thread up to continue the discussion started here, about whether it's appropriate provide a default implementation relying on
To set expectations clearly: the proposal has been accepted and the default implementation will ship in Swift 5.1. There is no possibility of it being removed from that release, given the point we are at in the convergence of 5.1, regardless of the direction of this discussion.
That does not mean that it must remain the default implementation forever. Later releases could easily deprecate or obsolete the default implementation, especially if signal from real-world usage shows it to be problematic. My recommendation would be to wait for that signal, rather than debate hypotheticals in this thread.