Also my understanding is that RustAnalyzer has to compile all Rust macros so it can check them properly. That’s not something that a lot of static analysis tools do for things like C++ templates
Personally I think the “compiling Rust is slow” narrative comes from comparing it against scripting languages like Python. If you compare compiling Rust against compiling C++ code of similar complexity, I think Rust will come out very favorably since C++ templates and headers tend to carry a huge compilation burden.