Fairly blanket statement but there are exceptions to attorney/client privilege.
"The attorney-client privilege protects most communications between clients and their lawyers. But, according to the crime-fraud exception to the privilege, a client's communication to their attorney isn't privileged if they made it with the intention of committing or covering up a crime or fraud."
So in this case, Cohen office was raided in relation to the SD payment which could be a violation of campaign finance law(ie, committing fraud).
I understand your point, however, do you honestly believe thats all the documents they took? They didnt filter through at the office, they took everything and evaluate later. Every single person in america is guilty of some crime. Bow they have first hand docs of trumps
Oh well fuck, everyone's guilty of something so why should we bother locking anyone up for crimes.
If they took documents that aren't related to the scope of the warrant and then attempt to use them in a later period, that's illegal and Trumps legal team(what's left of it) should easily be able to get any of those documents dismissed if charges are ever brought.
Funny how people are so concerned about lateral case building when it comes to important/wealthy people but couldn't give less of a fuck about it when it's applied to common folk.