That’s the only thing you base it on? First of all it has, by far, out of all the other current big three’s earned its spot. I honestly don’t get how some people can say that black clover is even up there. An anime can be good like demon slayer, but it needs more time it literally aired this year. It was announced in WSJ in June 2018 (I think I’m not sure) but we didn’t get any content until this year. I’m not saying it’s bad or that it’s impossible to surpass snk, but snk has proven time after time how great it is with the music, art, story, and this excludes the manga. Kimetsu no Yaiba has released like 12 episodes and it hasn’t released it’s second season yet so we can’t even know for sure if it will “dethrone Shingeki”.