Academic credentials such as PhD’s are milestones. The acid test is how the knowledge is used and whether it makes a difference i.e. is it transformative. The same is true of spiritual knowledge and business experience. Thus it is down to the individual to actualise the essence of what they have imbibed and should not feel inferior or compare themselves with others.
Excellent examples are Prophets such as Jesus (pbuh) who was a humble carpenter or the unlettered Muhammed (pbuh) who was a trader. They went onto make history that continues to this day.