If you're interpreting the scores as "goodness" you're missing the point, yes. Your concern seems to be that efforts to dispel that perspective are sparse.

I think this would help people learn about the various politicians in the same way that fantasy football players learn the stats, strengths, and weaknesses of individual players. It turns Congress from a two-headed behemoth that regularly doles out pain and suffering except to a privileged few, to a cacophony of opposing voices that each are relatively consistent (with some exceptions) about the things they tend to advocate. It sets up context for people so that when they see "Congressperson X says Y" they have a sense for how that aligns with the currents within Congress, within parties, and within people.