Why do superhero movies not boost comic sales?

Over in Japan, anime is often created entirely to boost the sales of its source material (manga, light novels, toys, etc.). And it works. So why are comic sales dropping even as superhero movies are still breaking records? Also some background on #ComicsGate .

Source:
www.newsarama.com/36750-retailers-become-heated-over-marvel-variants-diversity-in-closed-doors-nycc-panel.html

Check out Diversity & Comics:
www.youtube.com/watch?v=ijD7pUQ98Jg
www.youtube.com/watch?v=cBjTz7aBHz0

Gameplay from GOKEN:
store.steampowered.com/app/671260/GOKEN/

Intro/Outro by Walker Trips:
www.youtube.com/channel/UC71c43_lOSAOMPOKj0MpgCQ

Thumbnail from Shokugeki no Soma