I understand what their volume is getting and there is no doubt that they get a lot. But the thing is, you don't hold the private keys whenever you deposit to an exchange. It's a centralized exchange and you have no problem if you trust them. However, that fact won't change even if you trust them solely and the entire volume of theirs is getting billions daily. Look at the most popular exchanges in the past, they were also trusted but what happened..
I understand your point I use dex too, but you can't completely rule out cex influence and investment in the crypto space. They still play a major role. Since the FTX saga I think some exchanges are taking rensponsibilty rn. Bitget POR funds & merlkle tree, binance safu funds and I think bybit has some too. Those are examples. I believe we shouldn't ignore their effort because the past has been rocky..there's still more to discover mate..
Yeah, the centralized exchanges are doing better every time there's some issue that has happened to one of their kind. My point isn't about them improving their service because no matter what improvement they do to their customers and for their services. It won't change the fact that you will have no custody anymore when you started to deposit your funds there. But as long as the depositor knows that fact and can afford to stake that much USDT or any amount on them, it is his/her responsibility and risk that's being taken.