This has been the experience of many (not all) beginners I've worked with as well.
Confusion with redundancy more often than the concept embedded in the polymorphic version. It should be said that Functor is usually a titch easier to learn for new people than Foldable or Traversable even if they're not complicated to experienced Haskellers.
Another problem is that most books for learning Haskell don't incorporate much of the typeclasses under discussion, partly because of how new they are.
I don't think these caveats are a good reason to block or mutilate the BBP.
--- Chris