Worth mentioning that his manifesto mentioned nothing about anime from what I remember, all it was was a bunch of alt-right conspiracy shit like The Great Replacement and how dangerous mass immigration is.

It also included several pieces of plagiarism from other far right works including a piece from the Christchurch shooter.

Bunch of things that contributed more to his fucked up ideology than some Mongolian moving pictures.

I mean, it's entirely possible for one's ideology and opinions to be affected by factors we never even consciously realize. This particular example's still probably bullshit, though.