I'm gonna to say it: the Swift language had become a monstrosity.
At some point I hope it stabilizes without it being the end of the language.
I use Swift every day and while I still enjoy it, I think the language was nicer to use in its earlier iterations than it is now, which is a shame.
If I was Chris Lattner, I would be lying in my bed wide awake each night, staring at the ceiling, wondering how it went so wrong.