With anime, you can imagine a venn diagram with three bubbles.
a) Obviously for children
b) Creepy
c) Good
The surface level, "obviously for children", is a lot of what airs on TV. It's usually shounen crap, involves tournaments, powering up, and people punching each other. The americanized dub voices are annoying and the animation is shitty. I'd characterize stuff like Sailor Moon and Ronin Warriors and Naruto and Dragon Ball Z etc. into this category. This is generally the normie opinion on anime.
Then there is creepy - there are a ton of tropes like "girl who looks like a 10 year old is really 1000 years olds so it's ok to fuck her", "every male in the series tries to peep in the mixed bath", "harems",. "stealing panties and wearing them on your face is played for a laugh", "little sister really wants to fuck oniisan", "characters stick fingers up other characters butts for laughs." This is the bitter nerd opinion on anime, and almost any anime show you watch will have one of the tropes above guaranteed.
Then you have the third category, Good (which might be 1% of all anime if that). Every so often there's a cool show like Cowboy Bebop, Attack on Titan, Kakegurui, Konosuba, Death Note, Neon Genesis Evangelion - there is just so much anime that by law of large numbers, some of it ends up good. Keep in mind Sturgeon's law - 90% of everything is crap.
Western animated shows aimed at adults are pretty much just animated sitcoms - South Park/Simpsons/Family Guy/Rick and Morty/Archer are all fundamentally the same shit different box. That is changing a little - I did like Castlevania, but you know, anime is anime even if it's not drawn by Japanese people. Maybe one day we'll routinely get western animation that doesn't have a moron character making jokes about jews to make anti-antisemitism seem dated, who knows.