That's the way the algorithm works. The more people are staking, the lower your returns will be. But if there are more people borrowing than those lending (staking), rates will be higher than usual. At least, you'll be earning more than just saving your money in a bank. If you choose a good "De-Fi" platform that's audited by a security firm, then your coins will be safe for years on end. That depends if you follow the necessary security precautions to protect your coins against hacks and/or theft. "De-Fi" comes with a lot of risks, so I'd advise anyone to proceed with caution.
I think I'm better off staking stablecoins on "De-Fi" apps running on the ETH blockchain. It's a much safer bet than placing all of my hard-earned money on competing chains. "De-Fi" apps are constantly being improved by devs, so I wouldn't be surprised if it challenges "Ce-Fi" sometime in the future. Who knows how far this industry will go? Just my thoughts