Swift doesn't seem to be a bad language, but during my brief adventures with it I encountered a major drawback: differences between versions are so great, that searching the web for examples is problematic and you end up with many fruitless attempts and compiler errors. Apple's documentation isn't nearly as useful and readable as that of the Go team.
I took a long break from working with Swift and just started diving into it again, and even though there was two major versions since I last messed with it, it was pretty easy to settle into it, and I've only had to look up how to do things on a case by case basis periodically. Maybe that's just my experience, though, and others have a harder time with it.