Iger has to take some of blame by first promising shareholders a Star Wars film by 2015 when it wasn't even in preproduction yet and also being too aggressive with the release of Star Wars films every year when to be frank Lucasfilm and Kennedy weren't ready for it.
And now we know the GA wasn't either. It wasn't like (and he knew this if you read his book) buying Marvel or Pixar which already had a infrastructure in place to make multiple movies at a time. Lucasfilm had to pretty much reconstruct its movie division under Disney.