For me, I loved the world building that happened mostly through visual cues, and writing that was both emotionally resonate but also didn’t treat the younger audience it was targeted at as being unintelligent like so many other children’s focused entertainment both past, present, and future has/will do. However, it was also a show that was beautifully animated, well written, a touchstone for a lot of people, and actually grew up with the people that watched them. This was a short 15-minute show based in an absurd world of candy people, post-apocalyptic imagery, annoyed lemons, and lumpy space princesses. However, for me and many other people, there was one show that was the exception to the rule, and that was Adventure Time. I also found, like every generation before me and every generation from now on, that the next generation of animated shows from the 2000s never lived up to the same standard (spoiler alert it was because I was not a child anymore).
I grew up in the 1990s and like any child of that era, I am deeply protective of our cartoons like Gargoyles, Aaahh!!! Real Monsters, X-Men, Captain Planet, Beast Wars, and more.
TL DR – This is a beautiful end to a strong series, it might feel a bit rushed at times, but it packs an emotional punch and is one of the best series finales that I have seen