For me it’s about the “illusion of life” and how consistent it is amongst the figures. The jumping Brer Rabbit may have had the most dynamic “loop” of motion, but when everything was working, he really wasn’t any more animated than the geese, chickens, Turkey, or foxes in terms of mouth, eye, and arm movement. The “animated figures” (when working) were cleverly used in a way that they tricked the audience into thinking they were no different than the rest. Brer Gator was “sleeping”, why would he be moving? The possums were small and at a distance. Brer Bear was wiggling his arms, head, and body. The turtles moved their mouths and had the kinetics of the fountains. The Bear butts wiggled too.
Compare this to the mermaid figures and it’s quite apparent to see which ones are more living (Ariel, Ursula, Scuttle, etc.) and which look like animated corpses (turtles, fish, starfish). The same “tricks” splash used weren’t applied here, and thus there is a clear lack of consistency.
We won’t know until the “new” ride opens, but I think the fear is warranted given what we have seen from more recent projects.