Hello,
I would say so, but with most people I find that giving them something like a "delta" in what they say allows for them to speak in a fashion that I deem truthful. So if someone says that it is hotter than hell, and from the context of the conversation you can tell that you are neither in hell, the place is on fire, and there isn't the scent of sulphur, then you can safely say that the person isn't being truthful in their scope. Yet, if you can determine that the area is what you would describe as more hot than cold then you might be able to regard the comment an exaggeration. So you can imagine that the person is being overall truthful in their communication by applying a delta. Such that the reality is similar to what they are saying, though not exact.
To actually answer the question, I think that people are trying to convey emotion through exaggeration and not just information. So you can think of communication as a spectrum, and you have information on one end and emotion on the other. The more information, the less emotion and vice versa. So by communicating emotion over something that is strictly information necessitates a smudging over details.