It depends. What are you planning to do with these coins in the future? Since you have already done KYC, the exchange already knows who you are and how much bitcoin you have in your address/addresses. If you are planning to send the same coins to the same exchange at one point in the future, I don't see the need for a coinjoin. If the coins will be used for other purchases or everyday spending, it makes sense to break the link and start fresh. I repeat, will the coins go back to the same exchange in the future to be swapped for fiat or some other crypto when you are happy with your profit?

Several centralized exchanges have frozen withdrawals of their clients in the past after discovering that their coins have gone through mixers or coinjoin protocols. So it's safe to say they don't like it, and we will probably see more of the same.