`Arc`s show up all over the place specifically in async code that targets Tokio runtime running in multithreaded mode. Mostly this is because `tokio::spawn` requires `Future`s to be `Send + 'static`, and this function is a building block of most libraries and frameworks built on top of Tokio.
If you use Rust for web server backend code then yes, you see `Arc`s everywhere. Otherwise their use is pretty rare, even in large projects. Rust is somewhat unique in that regard, because most Rust code that is written is not really a web backend code.
If you use Rust for web server backend code then yes, you see `Arc`s everywhere. Otherwise their use is pretty rare, even in large projects. Rust is somewhat unique in that regard, because most Rust code that is written is not really a web backend code.