It takes forever to "properly learn" a language in my opinion, because it would mean the total emersion into the ecosystem and most prominent libraries built ar

It takes forever to "properly learn" a language in my opinion, because it would mean the total emersion into the ecosystem and most prominent libraries built around that language as well, and they will be always moving targets even though the language itself might be static. Go is no exception, and in fact there are only a handful of languages that can be ever "properly learned" if we are strict about that. The trick is not to properly learn, but to know how to learn enough of anything you need and make the best use out of that.