While it's true that some targeted attacks can lower the privacy of a Monero transaction, 2-3 churns (or the upgrade to FCMPs) will make even those nearly impossible.
It is arguably waaaaaay more likely that you'll have trouble when selling Monero for fiat (on the fiat side) than you getting in trouble because of the Moneros "history".
I am unsure about your last sentence. Isn't Monero "history" connectable to fiat (due to bad opsec, using KYC'ed CEX)? If so, then you can not say that Monero and fiat are separate. But IMO you are right, that fiat issues (dirty fiat received) is more likely issue to face. But that is what I am talking/asking about in OP. There is no way to significantly reduce chances of getting bad fiat for XMR? I am thinking about some KYC on a XMR buyer side along with some way XMR seller leave a review on a buyer in case trouble with fiat. The DEX I am unsure if supports KYC+feedback.
If so, then you can not say that Monero and fiat are separate.
??
Example Haveno: Ali from Istanbul sends Bob in Berlin 1000,- Eur.
Only Ali and Bob know what the 1000.- euros are for.
I am thinking about some KYC on a XMR buyer side along with some way XMR seller leave a review on a buyer in case trouble with fiat. The DEX I am unsure if supports KYC+feedback.
The main point of Bisq & Haveno is NON KYC! "in case of trouble" That's what security deposit is for. It is punished with XMR. For this reason, very little fraud has occurred in the last 8 years.
Somehow you contradict yourself. You want untraceable transactions first and then KYC.
Every dollar in the world has been used by criminals to purchase weapons or drugs. Often even supported by governments.
Cocaine can be detected on almost every euro note.
Fiat is fungible & Monero is fungible. So who cares?
Not always no. Lot of people are just normal people like you. But yeah this can happen. isnt digital fiat grand. Same problem as bisq, but way worse on bisq due to the bitcoin. Probably not dirty, not smart enough, maybe stolen accounts and people trying to reverse on you for profit. Safer to use cash.