ethereum biggest contender is binance coin.. bnb has a big potential as well as those in the top 10 list.. but the thing about this ethereum even though there are a lot of coins out there it seems that eth is so popular..
How exactly you think they are in competition with each other? BNB was build to be a DEX while ETH is doing so much more then that.
Though at the moment Binance is exchange while Ethereum is smart contract platform, Binance is lanching a new chain and you will be able to run smart contract on it and also compactible with Ethereum project, I can see in the future Binance try to force the projects on their exchange to move to their own chain. But I know there is still a huge room for growth when it comes to BNB tokens