Centralised exchanges get more users and would continue to get more users, infact the highest decentralized exchange(Idex) is now asking for KYC before users can trade, so I seriously doubt that decentralised exchanges would start making an impact in 2020, I see no signs of it at all, Centralised exchange are presently the kings and would likely remain so next year.
If IDEX can suddenly demand KYC out of thin air, they're not a real DEX.
Seems that StakeNet is about to make another jump in price despite the fact that the all market is down and struggling to maintain a stable price, this is what a strong project does when the market takes a dive , it stays strong. There are a lot of people talking about DEX lately and this could be only positive news that could reflect in 2020 in both volume and more users. I wouldn't not exclude Blocknet who is stronger and always push updates and waves even if they marketing lately seems to have issues regarding their vision.
Good call! Stakenet performed exceptionally well just 2 days after your post.
How can it be a year for DEXs when the Centralized exchangea like Binance, Upbit, OKEx, Bittrex are still waxing strong and further positioning itself to satisfy the regulatory demands of SEC and the US Market. Just recently, Some privacy coins were delisted from Okex, Upbit on the demands of the Korean Government. I think I am seeing crypto tilting further to centralization with DEXs like IDEX now running KYC for its users
The beauty of a pure DEX is that no outside authority can demand it be shut down. A year in crypto can change a lot. 2-3 can change everything.
The problem with decentralized exchanges is that you have to have a deeper understanding about connecting your wallets to the exchange's smart contract. And trade execution is really 10x slower than the centralized exchanges. Maybe someday but not now.
Wait til Lightning Network comes into the picture!