I'm very sorry to release an edit so soon after the last one, but one of my source lists updated and added a show I just had to include.
Anyway, here are my source lists:
https://editorial.rottentomatoes.com/guide/best-animated-series-of-all-time/
https://screenagewasteland.com/the-100-greatest-cartoons-of-all-time-100-91/
https://www.indiewire.com/feature/best-animated-series-all-time-cartoons-anime-tv1202021835/
https://www.menshealth.com/entertainment/g32380506/best-animated-series/
Enjoy!
