Cross out the "hardcore", lack of empathy is very much a core part of conservatism no matter which side of conservatism, social | fiscal, you lean into and by how much. If you're socially conservative you want every social aspect to stay as it is which proves inherently a lack of empathy. If you're fiscally conservative you want monetary value to stay as is (in terms of inflation and cost-cutting etc.) no matter whom it hurts (as long as it doesn't hurt you, of course).
Which is why I personally think it actually is (also) an intelligence issue, because the people that are not socially conservative and only fiscally conservative usually vote for the party of big government and military spending (R) which goes against anything fiscally conservative and as a "cool" side effect also proves to be detrimental to social values of different people and groups.
You probably know the quote by George Carlin, as its a told tale as old as day. I think the quote nicely illustrates the voting game in the US.