My understanding is that the language reference is a purposefully minimalist document that specifies the language (insofar as anything other than the CPython implementation does so).  So while better explanations of the implications of the language design are a good thing, they don't necessarily belong in the language reference.  (I'm not saying they don't, I'm just repeating what the intro says: "this is not a tutorial".)  In particular I am suspicious that statements that begin "in languages such as ..." don't belong in the language reference as it is currently written.