Not the parent, but you can certainly have an expression-oriented language without explicit statement delimiters. In the context of Rust, having explicit delimiters works well. In a language more willing to trade off a little explicitness for a little convenience, some form of ASI would be nice. The lesson is just to not extrapolate Rust's decisions as being the best decision for every domain, while also keeping the inverse in mind. Case in point, I actually quite like exceptions... but in Rust, I prefer its explicit error values.