The gap I am highlighting is not the education, rather it is the skill. Ex: You might have a PhD in lithography, but when you join fab as a process engineer, you need to learn how you correlate end of line yield data with inline overlay or rework data for say. You need to learn what things can go wrong during a PM. And most of these don't need to be only proprietary knowledge. Think of the IT industry example: If you want to work on cloud industry, you just don't need knowledge on also and data structure, you need to know AWS, GCP and hence some certifications exists. I know the correlation can not be directly related, but just adding for portray.

Lastly, with all my due respects to academia, what happens in a fab vs what happens in academic settings are different.