There are so many DEXs currently being developed, the first is probably from erc20, namely UNiswap, 1inch. Then came the bep20 namely Pancakeswap, Bakeryswap. From trc20, you don't want to be left behind, namely justswap and more, including from Polkadot, namely Polkamarkets.
The more DEX, the more variety we produce because cryptocurrency likes things that are decentralized.