Too Long; Didn't Read
Daml and Ethereum are used as blockchain open source to create applications that solve industry-level problems. However, there are several differences between the two platforms. When to use Daml over the public, you need a public mainnet and do not need privacy. You also benefit from the amount of innovation happening on public blockchain, which is inevitably faster due to more participation. Daml runs on many different blockchains (Hyperledger Fabric, Besu, Corda, VMware, and Daml Hub)