It is not that everything should go into the stdlib, but having syn, procmacro and serde would be a good start imo. And like golang having a native http stack would be really awesome, every time you have to do any HTTP, you end up pulling in some c-based crypto lib, which can really mess up your day when you want to cross-compile. With golang it mostly just works.
It isn't really in the flavor of rust to do, so I don't think it is going to happen, but it is nice when building services, that you can avoid most dependencies.