I think your conclusion is on the right track. Syntax sugar propagating results is in a way equivalent to exceptions. What you are missing it isn’t just equivalent to ordinary exceptions. It’s more equivalent to checked exceptions. A very powerful concept, that unfortunately got a bad rap, because the most widespread implementation of it (Java) was unreasonably verbose to use in practice. You might claim Rust is still too verbose and I don’t disagree with that, it’s a big improvement from Java at least, while at the same time providing even more safety nets.