> GC pause ... sufficiently low power hw .. cheap phone Yeah, but even high-powered hardware can take a "major" hit from a GC pause when your application is extremely latency sensitive. IMO it would be great to get folks who write the enormous base of existing realtime apps driving critical devices everywhere to sit up and take notice of Rust. EDIT: I mean to say that many of my colleagues who write realtime software…
That's true, but high-powered, abundant-RAM realtime applications can use approaches that are cheaper than Rust's. See, e.g., the interesting work currently being done updating realtime Java[1]. The idea is that memory is composed of a few kinds of lifetimes: eternal, scoped and GCed-heap. Scoped memory is basically nested arenas, and GCed heap contains objects that are used by non-realtime portions of the app (which, even in realtime systems, may comprise the majority of code, especially when the system runs on large servers).
An approach like Rust's, however, is crucial when the application is RAM and/or energy constrained.