Golangs web server is production grade and used in production. (Of course everyone uses some high performance proxy like NGINX for serving static pages, that’s another story.)
Technically you are right that java has no production web server, which I don’t like, OTOH Java has standard APIs WebServers and Spring is the defacto standard for web applications. (I totally would not mind to move Spring into the OpenJDK.)
My point is simple: Instead of having Rust edtion 2020, 2021 etc. and tweaking the syntax ad infinitum, I’d rather have a community which invests in a good/broad standard library and good tooling.
The only platform widely used in production w/o a big standard library is Node.js/JavaScript, mostly for historical reasons and look at the problems that Node.js has for a decade now because of the missing standard library.