The safest place for stablecoin staking and good profitability through stablecoin staking are 2 different services. Don't try to find it all in one service, where everything will be better than others. They do not exist. If it's reliable and stable stablecoins staking pools you're looking for, then you need to go to Curve. They don't have the highest interest rates, but at least their pools specialize in stablecoins and there's always good liquidity. They had some security problems this year, but it wasn't about the pools themselves and the vulnerabilities in the smart contract.