Anyone can be caught in the middle of this "war" without having done anything bad. Here is an example: John uses eXch to swap A to B. John then sells his coins for goods and services to Bill. Bill deposits the crypto into an exchange that now considers anything in connection with eXch do be 'dirty' and 'tainted.' The exchange blocks/confiscates Bill's crypto and the person calls John a scammer, requesting the money/goods back. John is the one who sold him those coins. Bill doesn't know or care about the history that lead up to eXch becoming the bad guys. All Bill knows is that he invested money into something and now he lost it and it was taken away from him. It's ugly for both sides.
This is exactly the reason why money must be fungible:
This site explains very well what it's all about:
Coin validation proposed to offer as a service to trace coins and try to give you a rating about how the history of the coin from your point of view and to offer that as a service to businesses. I think this could be quite dangerous because it goes back to that 17th century court case where now you could receive a coin that is perfectly valid at the time that you receive it, but a few weeks later a crime is uncovered and now your coin is tainted. So if this coin validation service is advicing many of the merchants where you would want to spend your coin at, it's tainted and now the merchant would refuse to accept your coin. That's a strange experience for you; you're holding a coin that you might have to sell at a discount to get rid of it. The aggregate effect of this might create a run on the bitcoin price. So it reopens this long-set legal principle that currency or currency units are all equal.
I can't stress enough how important this is!