I disagree with the premise of automatically dismissing sloppypasta just because it is verbatim LLM output. The sender could hypothetically have spent real effort in the chat interaction that led up to the ctrl-C moment, could have spent real effort weighing all the points raised and thought to themselves “this is all valid stuff to consider, let me forward it to my colleagues and see what they think for some additional human input on the matter.”
In such a case, I think that spending extra time to scrub the output of em-dashes or other slop is just virtue signaling that “I am man, not machine”