I guess there are more traders who "trust" centralizes exchanges because they feel they are safe with them, specially centralizes exchange in the top 10. However, we can't discount that fact that they are prone to manipulation and even hacks.

Personally though, I used a mix of exchanges in my trading, take advantage of most centralizes exchanges feature, but I don't put all of my funds in my exchange wallet. And then I go with decentralizes because there are coins that is so cheap and I can play around with just small capital and then get out as fast as I can get. Sometimes I sell them all on that DEX otherwise I will transfer it to centralize exchange and continue my trading.