About the context you are entirely correct. As I have said many times context does NOT equal proof. Not even close. The objects exist. There are many as you say that truly resemble fish and insects. That is because that is what they are supposed to do. The zoomorphs are in a lass by themselves and since the 30s still are Some like myself have seen a strong aircraft resemblance. Vertical and horizontal tails and correct proportions (not looking like any insect) suggest airplanes. The context is NOT there to dismiss them. A new context is needed to explain them. Simply put the artisan who created them (and there is a set of similar ones) either saw them as airplanes or was very lucky in his creations.