Lending & Borrowing is just a very small part of DeFi. DeFi is as diverse as the current economy: buying and selling, renting, investing in startups, projects, companies, apps, transferring money, donating to charity, participating in insurance, designation of inheritance..., simply absent of national government. At the moment we have only discovered a very small part of DeFi's capabilities, and most investors see DeFi only as a way to make a lot of profits in the short term.
And since the investor's intentions are inconsistent with DeFi's real mission, I think investing in DeFi at this moment involves a lot of risks.