I think Lattner saying that just confirms there are concerns.
The only people who seem to be saying it will continue are people outside Google. Crucially there's no one within Google saying they use it for internal projects.
And it's a good news - Swift is a niche, vendor-locked language. Using something like Rust for production level and something like Julia for R&D stage is a better fit.
I suspect it will drift along like the Java TensorFlow wrapper. Useful in some specific circumstances, but unused outside that.