It's very easy to spot the error here, compared to for example a segfault.

That's damning with faint praise if I ever heard it. (And it's not even true; undefined tends to propagate further, the segfault usually happens closer to the actual error. Not that I'm defending languages that segfault by any means)

Not to mention a SEGFAULT in Rust is a bug in Rust the language/std, not your program (unless you're writing unsafe code, which is pretty much never).