So, every now and then I see a post about the beauty of a decentralized exchange. Well here's the thing. You can't get USD on a Decentralized Exchange, adding new coins to trade will always be a headache, and since there won't be any censorship, scamming with new, random, 2 day old altcoins will be abundant, among other things
Decentralized Exchanges sound good in theory, but in practice it just isn't plausible.
Decentralized Exchanges can works, but never replace the Centralized Exchanges.