DeFi itself is safe, but there are a lot of scammers around these projects, there are a lot of fake airdrops on Telegram that offer you DeFi tokens for simple actions, for example, fill out a Google Form with the Eth address and Telegram name, after filling out you are asked to send a little Eth to create a liquidity pool on DEX most often they do not have a token contract address. If you are asked to submit to Eth, they are scammers, do not believe them.