What’s going on with it is that the ordinate axes are solely subjective criteria. In the subjective context, they are subject to the interpretation of the chart’s creator.
If they asked, "On a scale of 1 to 10, how strongly to you believe in a creator who influences events in the world?" or "On a scale of 1 to 10, how likely are you to base an important decision on what you feel is right in God's eyes?" or "How often do you go to church?"
These would seem like objective measures of Secular-Rational Values and Traditional values. No?