I didn’t read EY as making that point. The ‘hit points’ analogy suggests that he’s giving money priority over other things. Am I wrong?
In any case, there are some things that don’t seem measurable in dollar terms: how much money would I accept to drop X% in social status or Y fewer friends? I have no idea. I’m not suggesting that people don’t trade these things off, just that money is not a neutral currency with which we can compare the value of any two things. It allows for a imperfect but useful comparison of the subjective value of things for which a market exists. I know how much I’m willing to pay for a tomato or a computer because I’m accustomed to trading money for tomatoes, and thus I know that a marginal computer is worth more to me than a marginal tomato. I have no idea how much I would pay for a friend, in terms of money or tomatoes, because I have no experience trading these things off against each other.
Surely, other things equal, your best estimate for future voting is current voting. It’s more likely that another 20 will upvote than another 20 downvote. If you’re only concerned with the outcome, your best strategy will be to downvote. Of course, you may feel really bad if you downvoted a comment below what you think it deserves, because you were responsible.