Score voting results in tactical voting where only the most extreme scores are given, instead of revealing their "true preferences" on a grayscale. In fact, those who provide honest scores are disadvantaged, because the deciding-power of their vote would be lower than those who purposely exaggerate their scores to the extremes!
It works in situations where there are few voters and their votes are all publicly visible.
Score Voting is the superset of all voting methods. It is quite alright that some people would vote that way, an equivalent style to an Approval ballot. It is difficult to argue that more resolution is worse -- we desire more resolution in our phone screens and monitors, because we get a clearer picture.
HN is populated by many software engineers, we understand the principle of GIGO - garbage in, garbage out. Voters can be asked for an ordinal preference order or for approval. 99% of voters have these and can explain their choices (which isn't to say their choices are necessarily logical/rational).
Voters do not as a rule have a mathematical score for a candidate, excluding the case where they score equivalently to Approval.
Take a candidate which you did not vote for but do not hate, is your score for the candidate 1, 2 or 3.141529? Can you give an explanation for your score and why it is that exact value and not a bit higher or lower?
Asking people for information they do not have (a mathematical score for each candidate) leads to GIGO - unless just about everyone does Approval, in which case Score's just a more complicated, worse version of Approval.
While it's not my first choice, we could offer multiple versions of ballots that were translated to Score Voting canonical ballots. If you want the deeper resolution, you can have it. If you want to do FPTP you can have a ballot that masks a Score Voting ballot and simply votes just one person a 99. If you want an approval voting ballot, it masks a Score Voting ballot giving all your choices a 99. Score Voting is still the superset, the appearance would be cosmetic -- however, I am willing to concede that confusing ballot appearances do affect outcomes.
It works in situations where there are few voters and their votes are all publicly visible.