This is mostly only true if you're writing a network service or maybe a CLI tool. Which is fair enough, since that's what Go is primarily for, but Rust aims to be, not just usable, but the best option, in a broader variety of domains. It wouldn't be feasible to have a batteries-included stdlib for all of them. (Python historically tried, and the results have been rather famously unsatisfactory.)
Also, even network services benefit from things like OpenAPI for type safety, and you don't get that from the Go stdlib.
Also, even network services benefit from things like OpenAPI for type safety, and you don't get that from the Go stdlib.