That's one thing that annoys me about Cartoon Network but also what makes it easy to discredit lists. I can look up Top 10 or Top 20 or Top 50 anime lists and 99% of them contain Toonami/Adult Swim stuff.
Really? So you decided to write up a top 10 list and your only source material is a time slot that showed 20 or so anime? Get off the internet.
Reviewers need to cut the mainstream crap and actually get out and look for anime. There's a lot of crap out there from the 80s and 90s. There are also the old old old anime where everything's blocky and there are no in-betweens (Speed Racer, Kimba, GeGeGe no Kitarou G1). The really deep or moving anime rarely make it on the lists. Typically it's just stuff that someone's friend nerdgasmed over, like Ninja Scroll for example. Good movie? Of course it is! Great movie? Not really...
Hikaru No Go: On maybe 0.2% of anime lists out there. Excellent show based on a manga based on a board game that went on for many seasons, each of which I have watched. It actually had/has a fan following, yet it pretty much never makes a top anime list. Why? Because it's about a board game instead of ninjas and boobs.
Nekojiru and Astrofighter Sunred: Saw these on the same list. The guy's list literally blew my mind. Great animation? Almost no animation at all! But two of the funniest shows I'd ever watched.
Grave of the Fireflies: This makes a lot of lists, but still not enough. Is it a great anime? Not particularly. Is it a must-see? Seeing as how it's 100x better than the live-action version of it, yes. It's old. It's by Studio Ghibli. And it makes grown men cry.
Makoto Shinkai's films: He's gaining popularity slowly, but his early works are superior to most of the stuff Toonami/Adult Swim airs.
Little Nemo: No, this isn't an American cartoon, it's anime. It's childish, but the animation quality is superb even by today's standards. Oh wait, we don't have standards today.
GeGeGe no Kitaro and Hakaba Kitaro: Certain countries have had these series translated and even aired on TV. 90% of Americans have never even heard of them, while about the same percentage of Japanese have. Great animation? No. Great storytelling? Yup, at least G2 and G3.
I'll try to be fair. I mean, 90% of my favorite anime have been between 1985 and 2005 because, well, I stopped watching anime as much after college due to work and having no internet at home for a while -- mostly work, though. I do look up the movies that come out and some post-2k5 series do make it into my faves list for a time. It was hard to find fansubs that interested me and that were available online. Most anime I watched was on VHS. Eventually digital fansubbing became popular and more options were opened to me, but after college and with slow downloads, it was hard to hyperload on fansubs. I had no TV at home, but everything I could have watched on CN in the years after college I'd already seen on VHS without crappy voice acting. The stuff I had easy access to in those years that I moved out of my parents' house and got internet were dominated by shoujo and yaoi fansubs, or subs of mecha anime that I never really had interest in. Every so often I'd find one that actually piqued my interest past episode 1, but without my anime club I couldn't get back into it as much as I had been in college. The only anime club I could find near me was for high schoolers... "Yeah, officer, I swear I'm just trying to watch anime, not stalk underage girls!" Right now, Wikipedia is my friend; I search award winners and then download those. Or Anime Encyclopedia, sometimes, which was how I found out about Haibane Renmei. Every once in a blue moon YouTube actually suggests something worthwhile, too. But for the most part, the new stuff doesn't pique my interests because, well, I guess because no one else is watching them with me. Well, that's not entirely true. My brother is obsessed with anime for some reason, but most of the stuff he watches is harem anime crap. Since he doesn't know English that well and is just homeschooled by my mom, he thinks good anime is boring.