What I like a lot about it is the fact that many series follow a continuous narrative. Compare it to western animation, which is usually very episodic, and usually restricted to comedy only. That being said, I still like western shows too, and there are certainly anime that are more episodic, and of course lots of comedy anime exist. But most of my favorite series like One Piece and JoJo are simply unlike anything that we see in the western world. Stuff like Steven Universe is somewhat of a comparison, but even then there are many episodes which don't drive the main plot forward at all and are, you guessed it, episodic comedies.
Aside from that, I like the art styles that a lot of manga/anime have. Again, western animation tends to differ greatly, focusing on much simpler styles with less detail. And there's not necessarily anything wrong with that, especially when they are focusing more on comedy than action, which is expected to be more visually impressive. To be fair, I've never ventured into the world of western comics, so I can't really judge the kinds of art styles we see employed there.
But yes, overall I'd say that since Japanese comics and animation developed in a different way from those in western society, we can get a lot of different experiences that simply aren't offered by the stuff that comes on Cartoon Network and Nickelodeon.