The "517" designation is often a defensive measure against legal liabilities like (Children's Online Privacy Protection Act) in the US or the Online Safety Bill in the UK. By explicitly labeling content for 17+, website operators accomplish three things:
A website hosting both 5+ and 17+ content must implement (self-declaration or algorithmic inference). Failure to separate audiences risks regulatory fines (e.g., FTC fined YouTube $170M in 2019 for COPPA violations related to child-directed content).
"Experience the nostalgia of the 50s, 60s, and 70s with our vast collection of classic movies, TV shows, music, and games"
: While streaming services often fall under Code 5162, Code 517 is closely linked to the distribution networks that provide this media content to users. Census.gov