Perhaps the Go community should take a look at JEP or PEP to better document features and their life cycles and statuses overall.

It depends. I read JEPs quite often as part of my job. They are nice as a sum up of the intent behind the feature but they kind of hide the discussion and commits. Also one Java feature may encompass multiple JEPs.

Go‘s github discussions on the other hand, give me live-view of the latest state of the experiment. I find both useful and don‘t prefer either.

That would be asking too much, learning from older languages experience.