I don't think there's a bright line dividing systems programming problems between GC and non-GC languages. We use Go extensively at FullStory and it works great for a large class of problems. Rust has a compelling story for spaces where GC makes life harder or just isn't feasible. I will say that Rust being usable without GC does seem to put it in a better position around interoperability than languages with a GC, since composing language runtimes and GCs properly is a really challenging problem.