Anime for adult

Realistically speaking most Anime is targeted towards teenagers. There are many exceptions. But even anime rated 18+ are usually only so becasue of fan service not because they have mature topics in them. One Good example of a mature anime would, off the top of my head be Psycho Pass It touches on some very philosophical ideas that a younger person may not fully understand. So yes Imo Anime is mostly for younger people.

Source: Been watching Anime since I was literally 3 years old, Grew up on 90s anime.