The takeaway I’m getting from this thread is that George did intend for the Jedi Order to be flawed in the sense that they had a false sense of security and so failed to stop the Sith when they had the chance, but that George didn’t intend for the Jedi ideology itself to be flawed. That was an EU concept.
But Lucas knew what the EU was doing and even had a hand in directing it (though no creative input). Also, it is not the ideology that is flawed, but the institution and traditions. Good teachers must tailor the lessons to an individual student’s needs and abilities. This is why at the highest levels of education, teaching is one on one. As the Padawan is to the Master. When you expect all students to meet the same standards, you have a flaw in your institution.