Also, I don't think any in-universe content can easily be rewritten as out-of-universe, you'd need incredibly detailed sources for that, if I interpret policy correctly. A section describing the character traits of some alien race would need to be rewritten along the lines of why and how the authors/designers/directors made the character that way. In most cases, sources like that don't exist - which shouldn't keep us from implementing the proposed guideline changes. The basic premise is that in fact there is a lot of unsuitable material, we just need plausible syntax to get rid of it while preserving as much useful material as possible.
The in-universe statement: "The Blogaveen race has blue hair and green eyes." can be rewritten out-of-universe as: "In Episode 17, a member of the Blogaveen race is portrayed as having blue hair and green eyes." That statement is perfectly OOU, but doesn't require anything but the primary source. Obviously, information about the creation of the character would be good, but the absence of it doesn't make the statement IU.