I was referring to hinkley's idea for using Rust to write GCed VMs. As to other safety features, those are easily added to cheaper GCed languages. Memory is the hard bit, and if you can afford a GC, it is usually cheaper to just use one. As to RAM being costly, I think RAM is one of the few things that is getting very cheap relative to other resources, and GCs require less and less tuning; working hard to avoid a GC when you can afford one seems to me like the mother of all premature optimizations. But I see no point in debating the issue too much. Every company would make its own consideration about which approach is cheaper.

In any event, there are certainly very important use cases that simply cannot afford the power and RAM overhead required by a GC (again -- latency is not an issue; if you have the resources, there are cheap ways of getting extremely low latencies without doing away with a GC) and those use cases would benefit tremendously from a safe language.