Speculation time! Chris Lattner designed Swift while he was at Apple. Apple seems committed to it, and Chris seems to spend his time making it a language that isn't Apple-only. His stint at Tesla was maybe short because Tesla didn't want to adopt Swift. At Google, he got to start a project with it, but him leaving suggests it didn't catch on. SiFive is small and hardware ramps are slow, so maybe he's given up on the Swift-world-domination plan. Again, this is all speculation.
