Is Cosmos a competitor to Ethereum?

No, Cosmos embraces Ethereum. An upcoming project called the Gravity Bridge allows you to bring ETH and ERC20 tokens over to the Cosmos Hub and send Cosmos IBC tokens into the Ethereum ecosystem. Other Cosmos projects include Ethermint that brings the Ethereum Virtual Machine to Cosmos and Sommelier Finance (SOMM) that reduces Ethereum transaction costs for decentralized finance (DeFi) applications.