Every coin has their own uniqueness. These uniqueness makes them different. Bitcoin with the blockchain technology, ethereum with the smart contract, and lots of other projects build upon them. USDT is giving a balanced crypto market with no losses. IOTA is with a fee free transactions, to mention but a few...
All these are their uniqueness, which makes them special. When it comes go price of these token there are lots of token that are of more worth to ETH. The best coin is from your own view.