I'll probably hold off on learning Rust deeply until they have async/await as keywords. Most of the programming I do involves async, and I currently do my day programming in Dart, which is an absolute joy to do async programming in. They had Future-based APIs from day one, so the whole ecosystem was built around futures starting out. They've had async/await as keywords for over 5 years now. It's so ergonomic it's painful to go back.