Recent news events in the US have resulted in many headlines about "nude photos of young women" and variations.
[W]hy does this phrasing persist?
Quoting (adding emphasis) from Joseph Henrich's 2016 book, The Secret of Our Success: How Culture Is Driving Human Evolution, Domesticating Our Species, and Making Us Smarter: from p. 231:
[L]anguages arise from long-term cumulative cultural evolution. Like
other aspects of culture ... our ... spoken languages ... have evolved
via cultural transmission over generations to improve the efficiency
and quality of communication, and to adapt to the details of local
communication contexts, including ... social norms (like taboos).
From p. 232:
[A]mong our ancestors, cultural evolution accumulated, integrated, and
honed many useful communicative elements over long stretches of time
into increasingly complex repertoires[.]
Presumably this phrasing persists (within our local communication context) because, in our attempts to communicate this general idea, each of the exact communicative elements "nude photos" and "young women" contains enough pressure (perhaps arising from social norms) to survive (rather than dropping to the cutting room floor): perhaps this is because both elements are salacious, or refer to some current political themes, or otherwise have impact, which is presumably desired by the news headline editors. By this phrasing, the editors communicate to us a doublet of ideas: that the women are young, and that, normally, they are not nude. Presumably they are nice, acceptable people. This meaning is less conveyed by the phrasing, "photos of nude, young women."
So, the fact that both communicative elements persist (or that this phrasing persists) follows no grammatical rule: i.e., it is idiosyncratic (rather than idiomatic, precisely speaking).
Also, the very fact that our language productions typically follow various grammatical patterns is itself merely the result of our idiosyncratically weighing those grammatical patterns along with many other cultural factors, in our attempt to achieve success.