I think it's a desire for minimalism. In a world filled with websites saturated with ads, clickbait and constant attention grabs, this is like walking from an overcrowded city street into a Zen garden.
Well, if someone opens this app their goal probably is browsing lists of anime, so the attention grabs you're hinting at are intentional, and thus not 'attention grabs' in the sense the parent commenter is talking about.
