Er yeah technically the event loop isn't part of Rust, just the async/await syntax. But it's implied that you're going to use some event loop with it.

No, it's implied that you're going to use some sort of async runtime with it... said runtime can be simple real threads, a thread pool or virtual threads and there are implementations for all of them. And even then, it's super easy to start a new real thread in rust, around any async runtime.