Very good posts Jal90 explained it better than I ever could. I was so insecure back them. Notice also how 90's Ace reflects all the stigma regarding Japanese visual culture that is present in the Western countries. Also also reflects this problem present in US culture (and actually in many other Western countries as well): https://www.sott.net/article/313177-...own-of-America, https://www.thedailybeast.com/americ...t-of-ignorance,

Oh, just to clarify, in anime shows are classified as "for adults" or "for kids" (or whatever) just according to their source material, which usually is the manga magazine. Manga magazines usually serialize many different series and have a specific demographic target (adult males, teen males, adult women, teen women, etc. are the usual ones), so everything they publish falls automatically in that target, no matter how is its content or genre. That's why anime original works on the other hand don't have an official demographic classification; like most Ghibli films, for instance.
Manga I think are one of the very few media products that have official "target demographic" classification. Movies have restrictions on minimum age but that's not mean the movie is made for children or not (like 2001 is classified as G), same with viodeogames and TV shows.

I was reading a survey of manga publishing written in 1996-1997 in Japan that also detailed not only the broad target demographics but also that magazines are made for people aged 20-25, aged 26-30, over 30, etc.

He also said that shounen manga is actually read by people from all ages, from 12 year old boys to 30 year old salary men to people over the age of 60. Indeed, Japan's former prime minister was a big fan of "children's manga" and often read manga aimed officially at teenager girls like Fruits Basket while awaiting for his flights.