My main gripe with Go is that a large percentage of first-party documentation is not kept up to date well. If you dive deeply into Go's concurrency patterns, many of the recommended readings are old blogposts from 2014-2016. When the behaviour of the internals change, these blogposts are not clearly marked as deprecated either.
For example this post
should clearly mention that it can still be considered current up to the latest version of Go. First-party documentation needs to be held to higher standards.