That's wrong, condescending and misses the point. Wrong because the developers were not cut off from learning what was learned by others. Condescending in the way it implies that there's a royal "we" of people that should be consulted whenever any programming language is conceived. And it misses the point because some types of learning are learned better by making the mistake yourself rather than accepting the wisdom of authorities.
Anyway, I don't see how Swift's life cycle is any different from other most other languages, except that its inevitable celebrity has been tempered by its parents' protectiveness. The number of people expressing interest in nurturing a language in its formative stages grows in proportion to its viability. Swift went from experiment to viable as soon as it got chosen as the path forward from ObjC.
> just an hour long conversation could've made a big difference
Apple has huge numbers of programmers on staff, including many compiler hackers, many kernel hackers, many with practical experience building and maintaining APIs and developer tools. They employ literally thousands of programmers who will be end users of Swift. To suggest that your opinion is more valid than theirs is hubris.