It is an interesting question. For man, "I think therefore I am" is the keystone for a belief of meaning. A machine comes into existence with the flip of a switch and by and large there it is. Mankind on the other hand learns to think existentially. Can a machine do that? I dunno, but it seems to me without the underlayment of homeostasis or a desire to for comfort (which is such a conceit, how can a machine begin to understand that concept?) that emotions would always be an alien concept to something not biological.
I have some issues with your comfort hypothesis. It seems true but, then again, much of human culture is based on the opposite. Which is weird. The warrior, the elite athlete, hermits/monastics, the adventurers, wearing the hairshirts, sexual chastity or monogamy, moderation (or even abstinence from "worldly pleasures", alcohol, drugs, etc.) Or, maybe, we idealize (or idolize) those types of people because they are NOT the norm and so are considered special etc? Certainly it seems logical, and seems to be factual, that comfort (at least beyond self-preservation and pro-creation) is the main goal. Or, I guess, on the individual level (and societal level) "comfort" can actually be a negative thing (a beaten kid might consider the beating some kind of comfort in the familiarity at least. A slave, or these days prisoners, might be comfortable in their captivity due to routine and, relatively, regularized system and meals/housing versus suddenly freed to an uncertain future?)
That this could be changing in more modern culture (but even now we idealize, or even participate, in things like extreme sports, camping, long hikes, wars, hunting, etc most of which aren't "comfortable" but can involve risk, high-stress, or at least discomfort.)