During the 2020 survey there were two versions of this operator on the table smart mix and F#. A few months later the committee advanced a third option Hack, which is kind of like smart-mix but always requires the placeholder token.

I suspect that many developers expressed their desire for this operator under the believe that it would make their style of programming easier, which F# indeed does for many code bases, particularly those that use libraries such as fp-ts or rxjs.

However the advanced version fails to deliver that