Take backend dev for example: unless you're trying to squeeze the last drop of performance from your CPU, most concurrency issues are usually dealt with at the middleware level (DB, Queue, Nginx, etc), and most performance issues are usually I/O related.
I'm currently evaluating developing a cross-platform mobile native library using Rust, but i really don't see myself inflicting the pain of that language to the rest of my team.
Or maybe it's just a reflection on how active the community is ?
edit: i realize a lot of people are probably still coding in C because they have no other choice, and for them it's probably a good idea to switch. However, for all the rest i really don't see the point.