I do agree with most of this, specifically that a lot of is lost in this communication method. Most if not all of us have been taken out of context or someone has gotten offended by misreading our writings. Then of course this is the occasion word omission such "not" making a sentence come out the reverse of what we intended. In business, I would tell my staff the following "read what you wrote at least twice before hitting the send button". I highly encouraged them to take a break before hitting the send button as well because in our heads we think we wrote one thing when in fact we didn't.
As to the red X thing, I see that a bit differently; it just means someone disagrees with a statement, does not necessarily require an explanation and many times an offered explanation will only serve to further a "debate" when it is not necessarily needed. I understand that it can feel like a punk move, but I will be honest and say that I have done it and had it done to me, but I don't take offense to it.
As to the subject of this thread, I remain a bit confused by it to be honest (which I posted earlier).