Good points, wholly, and they evidence excellent perception. I agree with you as far as it goes, but I think there are cases where some folks are "offended" for no valid reason.
I'm not so sure I buy that, as I have had a lot of experience dealing with people who are "uber-sensitive" and far too quick to take umbrage at the slightest suggestion that they might have any degree of fresponsibility for why something is "borken". It's a little like when you remind your teenager to turn out the lights and they respond, "I DO NOT* always leave the lights on! How dare you accuse me of that? Who said I left the lights on! That's not true! Why are you picking on me?" Shakespeare, wasn't it?: "Methinks thou dost protest too much"
Hey! That's a good plan, just as long as they don't spend any money or resources that could be better used to provide services or hardware for other customers for that level of "coddling". That is the "customer service" model for far too many American business these days, and those costs have to come from somewhere. I actually like a host that is "frugal" that way,. even to the point of aggressively managing clients that demand more attention than is reasonable for problems that are not really part of the hosting company's support responsibility (such as third party scripts - as mentioned in the TOS). That makes for a better value for the rest of us.
That is another excellent point and I think everyone should try to be "less accusatory" in most circumstances; I'd also like to point out that neither you nor I even saw the email in question (the OP elected not to share it), so neither of us are really qualified to characterize the "tone" of the email. As you point out, it really doesn't matter- the receiver of the communication will generally characterize it in whatever way he chooses irrespective of what was actually said. In my experience, clearly "bad" tech support responses are usually shared by the recipient; I'm also dubious of claims that someone's communication was "condescending" or "accusatory" when they can't be bothered to actually report what was said or written.
That does nicely sum it up in my view, and I think you are "right on the money" with that assessment.
That said, the obvious question is, "Why even respond to these types of posts?", and there is a strong and somewhat convincing argument to be made that there is no worthwhile reason to respond at all. The counterpoint to that argument is that, in public forums such as these, it is so easy for a poster to unfairly and/or unreasonably vilify another (person or company), making no effort to substantiate or provide support for their statements (I call these types of posts "a drive-by bashing", that some balance is added to what others reading the thread see by taking the time to challenge, or comment on, the reasonableness, or voracity, of the post.
Meh...I'm not sure it makes any difference anyway to this poster (his mind is made up), and your post artfully points that out. It might, however, give a subsequent reader some pause before assuming that what was reported was completely accurate and fair.
So, not knowing what DreamHost's initial response to this poster actually was, or the ultimate source of the problem, I can only trust my own experience. My experience with DH Tech Support's demeanor and "tone" is that they have been unfailingly personable, friendly, solicitous, and proffesional. My experience in tracking down problems with third-party scripts is that is almost always the script itself, its installation, or its operation that is the problem (though, as you point out, that is not so much the relevant issue with this poster).
Caveat Emptor, YMMV, etc. - all the standard disclaimers apply. PAX