We don't have many real DEX options but Bisq exchange should be mentioned first, you need to download open source software and run it in your computer.
BlockDX is also decentrlaized but last time I checked it didn't have much trading volume, and I don't think it gain any popularity so far.
Few other P2P alternatives can work as alternative if you are using mobile devices, like Peach Bitcoin, RoboSats or AtomicDEX wallet.
I have used all three: Bisq, BlockDX, AtomicDEX.
Liquidity, user friendliness and easy to use is important. trading fees are important too.
Out of three, currently only working one is AtomicDEX. AtomicDEX for small DEX traders are fine, the fees are small, spread is wider than CEX, but definately a niche and very good to use to own your own private keys for most of UTXO coins and also BNB and ETH cross chain trading.
Bisq never worked for me, the deal breaker was high fees and poor liquidity even on DOGE/BTC pair. Bisq seems to be huge on Monero pair so that it is mainly a private coin dex there.
BlockDX has been dissappointing so far. It appeared to be great with bitcoin coin clone technology core plus masternode POS design. Somehow the light wallet Xlite was never materialized after many years. BlockDX would be great competitor to AtomicDEX if it delivered what it promised years ago. For me BlockDX high level DEX design seems to be very decentralized if their service nodes count goes up to big number.