I think he's trying to get people to short him. The protocol has pretty much the same mechanics as Luna / UST.
The only difference is Justin Sun has a LOT more money than Terra. They're small fish.
Would i short the man who bought this art piece for 78M+?

The problem is not how much money a project has. Matter is if your product concept is wrong that results in a broken financial model for your project. It in turn will be a deadly weakness of your project and at a right time, your project will be compromised to death because of that weakness.
The technical concept for USDD from Justin Sun and TRON is the same as of UST and LUNA from Terra. From the bailout of Terra, I don't believe investors (institutional or retail) will mind to spend their capital into USDD, if it is built on as a similar algorithmic stable coin of $UST.