I didn't quite understand. By which authority can they issue such a certificate? Who does this Bitcoin Professional give to the class? It's kind of silly to me ...
I agree, the point of bitcoin is to be decentralized and yet it seems people are unable to leave behind the old habits of letting someone tell them what to do, if you want to know about bitcoin then read the bitcoin whitepaper written by satoshi himself, his comments, learn how to code and read the development and technical subforum and you will learn more than what any course will teach you and the best part is that you can obtain all this knowledge for free.
In the best scenario the people giving this course know about bitcoin but they do not want to give their time away for free, in the worst scenario this is nothing more than a scam like the ones we see in the forum all the time.