Yes, I understand that DAG and Blockchain are not the same. However, one could argue BTC/ETH or Hedera none are absolutely zero trust, because developers could be a counter party risk within the whole system.
DAG and Blockchain are both DLTs none the less using more or less similar/compatible SDKs, so real world use cases would just boil down to security, throughput, UX and scalability for Dapps end users. Hence, both the DLT (DAG & Blockchain protocols) can build Defi ecosystems.