Unfortunately, this is one aspect of IoH that I really dislike. The jungle “natives” are the victims of an extremely racist portrayal. They follow the tradition of “the noble savage”, a people so much less human than “civilized” people, but acceptable because they don’t interfere with the desires of the villagers (such as building up the island).
Shea and Wada’s English is patchy, and their inarticulateness is made to make them look stupid. Both characters wear animal skins (of animals not found anywhere on the island), facepaint, and headbands, like bad caricatures of Amerindians of North America. If you look closely, Wada is even surrounded by flies, implying that he smells and has bad hygiene (which would be an extremely offensive concept to the Japanese, where “pretty” and “clean” are one word, and bathing has a long ritual history).
I could could go on and on, but in the end, Shea and Wada are still likeable characters. It’s important to note, also, that Shea is a hidden bachelor!