stable coin does not guarantee safe, let alone this kind of DeFi. I'm not saying it's definitely a scam, but if we want to match it with Terra USD they are not guaranteed with backups. I understand maybe they say that UST is backed up with bitcoin but the fact is stable their coin is falling. this is what makes it hard for me to trust DeFi.
all investments are very risky, especially if you invest in crypto currencies of course very high risk,
yes not only Defi or stable coins, but all categories such as PoW, PoS, and even Metaverse are also very risky,
if you want to be safe, my advice you can invest in a gold .