1.) It establishes the fact that fiction articles are
only notable if there
is out-of-universe infomration available
Information is neither "in-universe" or "out-of-universe", it's
just a
collection of facts. It's the presentation of that information which
is in- or out-of-universe, any in-universe content can be re-written
out-of-universe (although a large amount of in-universe content is
often a clue that the article needs trimming, so I'm not suggesting
blindly rewriting articles). I think what you're trying to say is that
there should be non-primary reliable sources in order for something to
be notable, which is probably a good rule of thumb.