I remember it took a me a bit of investigation to make Ruby call Go functions, but it wasn't really hard: https://dario.cat/en/posts/portal-between-ruby-and-go/

The argument about FFI and CGO was the most unappealing to me. If you really need to do that, it feels that at some point some decisions were made that weren't the right fit for the project.

Also, I feel that many arguments in the article are potential pitfalls for unintended side effects I've experimented in other languages, like Ruby itself. Keyword arguments are nice, but I know that they've bitten me several times.

Go forces the developer to be explicit about their intentions, that's why I also don't find something bad that your struct functions need to have the pointer receiver. It can be annoying when you forget, but that's what linters are for.