it is all about the control. using a decentralized exchange you are mostly in control of your funds and the risks of losing them are minimal. also you do not have to trust a third party with your money since you give up that control using centralized exchanges.

the reason for the hype is that there has been many centralized exchange hacks in the past that has made people uneasy to work with any of them.

there is another hype that should be confused with the one i mentioned and that is the hype of the tokens like Wave,... that is for trading purposes and making profit from their pump and dumps.