Those interest rates are very high. One basic rule in investing is, that if someone shows you a risk free high gain investment, there’s something fishy.
With over 10% interest, there has to be some very big risk.
I make no claim that anything is risk free, low risk, or any other characterization. There are different types of risks that are inherent with any investment. Cryptocurrency carries volatility risk, speculative risk, and risks associated with lack of insurance.
For example, deposits in a regular bank in the US are FDIC insured, i.e. the government guarantees you can withdraw your funds even if the bank becomes insolvent. Cyptocurrency exchanges do not have this protection, so that increases the risk of holding cash in these accounts. If the exchange goes under, you will likely lose your funds unless you hold the funds on the blockchain directly.
Cyptocurrentcy is highly volatile, especially right now. This carries a lot of downside risk, and various methods available in a standard stock exchange to mitigate this risk, such as covered call options or other hedge strategies are not available for cryptocurrency.
Cryptocurrency is highly speculative, and carries risks such as legal obstacles. Some governments are outlawing it completely, others are highly restricting it. There is inherent value risk in cryptocurrency in that in most cases, it's not backed by other currency.
Stablecoins mitigate
some of these risks. In the case of USD coin, that mitigates the legal obstacle risk (as Coinbase is a fully licensed and legal entity in the US) and the inherent value risk (as USD Coin is backed by US dollars). Stablecoins themselves mitigate downside risk as they're designed to maintain exact value of 1 coin = $1.
My assertion is that lending stablecoins to draw interest carries
lower risk than holding non-stable cryptocurrency directly. How that risk level compares to other more traditional investments is up for debate.