The fundamental thing is that no merge or consensus algorithm can somehow telepathically know the real world intent of its users.
CRDTs can best be thought of as a way to eliminate spurious and false conflicts, leaving only real errors. Without them anyone who has ever coded a data merge knows you tend to get a ton of noise.
So basically you have reduced the problem surface area.
Not the OP, but I'm guessing he's referring to, for example, two users each correcting a typo in a different location in the document. From the perspective of the text CRDT, there's no conflict, and users are likely to agree. Raising a "file edited simultaneously, choose which version to use" error would be a "spurious and false conflict" in this sense.
Note that from a different user perspective, say a code document, such a conflict is actually correct and desired. So it's all about context.
CRDTs can best be thought of as a way to eliminate spurious and false conflicts, leaving only real errors. Without them anyone who has ever coded a data merge knows you tend to get a ton of noise.
So basically you have reduced the problem surface area.