I see a lot of funny posts.
Centralised exchange are not dangerous to any coins but only to its users. To minimise that risk you need to be sure they are not scammers before you deposit coins to them and as fast as possible after you trade your coins to withdraw them to your wallet. Centralised exchanges are of same use to privacy coins and to surveillance coins. There is no difference.
One thing I totally agree. Privacy coins are not dependant on centralised or any exchanges. Since they have clear use case. Their use case is not just to be traded on exchanges but to be used in commerce.
But if there's a demand, people would trade these coins or tokens. They have a decent volume and it's still volatile, so judging that, it means people are trading it and exchanges are making money from it.