Don't forget there are also the peer-to-peer exchanges to look at, like Bisq. They probably can't compare in volume and yes, they take a lot of getting used to since you have to either wait for a good offer or make your own and hope someone with enough money takes it all.
While Bisq is definitely not 100% decentralized, it's still the best among the alternatives in my opinion. It's completely understandable how you access the Bisq exchange using a software instead of a website, but unfortunately this might be one of the reasons why a very small number of people use it. Liquidity and trading volume is really really bad though, but I think this will increase with time as exchanges get more regulated and as people look for more non-custodial alternatives to centralized exchanges.
