Of course there is risk, but they are not as great of a deal as you think it is. I am talking about transactions that deal with stable coins only, one of them is backed by a credible institution (Circle) and I am talking about a smart contract (Curve) that is being used already for over an year and is holding billions of dollars already.

Smart contracts are somewhat Lindy: the longer they are in place, the more of an indication they are secure. I wouldn't recommend putting your money on any new contract, but Curve is around for long enough that I don't believe that it will get hacked in the next years. Sure, it is not as "secure" as a FDIC-insured savings account, but it is not degen-type of investment either.