You make some good points, but I was specifically writing on the topic of voting due to empathy, with the expectation that the person doing so is doing so on be

You make some good points, but I was specifically writing on the topic of voting due to empathy, with the expectation that the person doing so is doing so on behalf of others, not on behalf of their own self interest. And that empathically voting on behalf of the Other means demonstrating less empathy toward one's Fellows. As you say, there are plausible rationales why my hypothesis wouldn't be the case.