People always blow out of proportion just have big Hanzo’s projectiles are. The fact is (and this was stated directly from a Overwatch developer - Geoff Goodman, I think) Hanzo’s projectiles are the SMALLEST in the entire game, tied with Genji’s primary.
https://us.forums.blizzard.com/en/overwatch/t/hanzos-arrows-hitboxes-needs-nerf-in-size/17397/16