I don't think they're talking about the language manual itself, which is certainly very good (though I have my quibbles with it), but the quality of documentati

I don't think they're talking about the language manual itself, which is certainly very good (though I have my quibbles with it), but the quality of documentation for packages/package ecosystems. Those vary a lot in quality: some good, some incomplete, some hard to access (another subthread here mentions cases where you have to know the implementation details of a package to know where to look up the docs), some poorly organized, some outdated, etc. It's not an insurmountable problem, just adds additional friction to the process and can make the experience more frustrating than it needs to be.