It's hard to know the truth in this space. Most blockchain development and discussion is driven by greed. Proof-of-stake has various problems, depending on who

It's hard to know the truth in this space. Most blockchain development and discussion is driven by greed. Proof-of-stake has various problems, depending on who you ask. In this case, as far as I understand it, the issue is related to large positions locked as collateral in DeFi. PoS security assumes that most of the available currency is used for staking, but the security assumption breaks if most of the currency is locked as collateral in DeFi (which can offer better interest rates vs. staking).