Yeah Toei kind of shot themselves in the foot with that one. Though it may depend on how far ahead in the production cycle they storyboard their episodes. Its possible that this scene was created before Hodi's reveal, since they may have reasonably assumed he had some sort of tragic back story to justify his actions. Though that still doesn't explain the other glaring problem of human pirates both strutting through the Fishman district like they own the place and not being immediately crushed by the incredible water pressure that should exist at that depth (one of them even has a musket, which would NEVER work underwater).
Also, what is the spoiler policy for commenting on the anime threads? I originally assumed mentioning the inconsistency would be a spoiler given that its not going to show up in the anime for 2 dozen or so episodes and was treated like a big reveal in the manga, but it looks like people are talking about it openly.