I understand your point and, sadly, we can't exclude the use of CEX at some point if we want to maximize the chance presented by the market which is the reason why some people use CEXs for investment
I don't agree with this the major reason why people decided to choose cryptocurrency is because this sector is decentralised, people are tired of being slaves to the the government, and cryptocurrency brings that freedom from surveillance and restrictions.
To further emphasis a large portion if not all those who are into Bitcoin mixing all do it because they value privacy and anonymity.
Centralised exchanges CEX are under the eyes of the government you would need to provide many private details about yourself that can be used to hold you down. Decentralised exchanges are the opposite.
So how do one who decide to use Bitcoin mixer for anonymity and private end up wanting to use centralised exchanges
There could be so many reasons why we choose to mix coins. Most time it is not because we don't want our identity to be tracked but it could be a way to prevent us from been connected to a particular wallet that sent us funds and
has been tagged as scam ruled by the AML watch bot.
There are so many reasons why people decide to mix their coins which one need to understand before trying to bring it from the view of Centralized exchanges.
For the centralized exchange to be in operation, that does not mean that they are trying to shift the purpose of Bitcoin which is meant to be decentralized to centralization. Even the CEX is more richer compared to decentralized exchanges if we look at it from another angle. The CEX offers so many features for users which are the reasons every investor want to have a CEX account.