I am sorry that I have a bad professional habit. I don't continue unless I get a good response from the one I talked to.
You are, in fact, right on the money. You pointed out the most critical question about learning and education.
However, if you read what you said one more time, would you be disappointed or even feel sad by the limitation of human learning? In my scenario, we evaluate what those 50 Ph.D. have accomplished at the end of the 30 years learning period, what then is the criteria of the evaluation?
Obviously, if any criterion is used, it must be one beyond the measurement of the amount (and the type) of knowledge. I always tell my students: College education does not mean to give you knowledge, but to give you method of getting knowledge. For undergraduate student, it means critical (logic) thinking and scientific method. Now, here is the next question for you to think about:
If a person already learned how to think critically and how to use scientific method to acquire knowledge (Ph.D. student or Ph.D.), what additional tool he can learn and use in order to educate himself better?
Use the same tool to repeat the same project can improve the quality of the product, but not to raise the product to a higher level. Those who have better tools not only can do a better job, but also can do a job of the next higher level. In order to be "better educated" beyond a Ph.D. level, one must hold the learning tool of the next caliber, which is better than those common ones, such as critical thinking or scientific method. Is there such a learning tool, if so, what would it be?
Step 3 will follow if I get a good response.