I've come to the conclusion that is because Apple can't release anything that may not look (on paper) as being "ready", since they built their image on attentio

I've come to the conclusion that is because Apple can't release anything that may not look (on paper) as being "ready", since they built their image on attention to detail and polished products - so in other words, a Swift 0.x. would not have seem polished/professional enough for Apple to release into the wild, even if it had all the present functionality.