> found no place in which C++ is a better fit than Rust, and so it's my "new C++".

Writing the compiler toolchains that Rust depends on, industry standards like CUDA, SYSCL, Metal, Unreal or the VFX Reference Platform.

There are places a language could be a better fit, but which haven't adopted it. E.g. most languages over typescript on the backend, most systems programming languages over Java for games.

Rust uses LLVM because it's pretty great, not because you couldn't implement LLVM in Rust.

Maybe cranelift will eventually surpass LLVM, but there isn't currently much reason to push for that.