Is Ocean Protocol on Ethereum?

Could you please clarify if Ocean Protocol is indeed built on the Ethereum blockchain? I've heard various discussions about its potential interoperability with other networks, but the initial implementation seems to have a close connection with Ethereum. Is there a specific reason for this choice, given Ethereum's current dominance in the decentralized finance space? Are there any plans to migrate or expand Ocean Protocol's functionality to other blockchains in the future? Understanding its current status and potential roadmap in this regard would be invaluable.