> Any scientist will tell you
That said, why would anyone think such scores could be a reasonably accurate representation? You are aggregating such complex situations and with that you kill off nuance. It doesn't mean the scores are useless, but need to be used carefully. I mean even look at the chart and you'll see weird things pop out. Ireland is ranked 5th by the "Freedom in the World" Index and falls into the highest binning for all 3 categories: economic freedom, press freedom, democracy. Yet New Zealand is 3rd, falling into the second bins for economic and press freedom. Further down you see the US below Argentina yet the US's scores are significantly higher than Argentina in each other category and the US is tied with Mongolia (who has a major problem with Press Freedom).
It should be quite clear that these scores are missing a lot of important details. Like the US definitely has problems with Freedom of Speech (and growing) but you can call Trump and Clinton pedos on the internet all day and nothing will happen to you[0]. Nuance is needed and treating these indexes as black boxes is just harmful to a conversation about freedom.
Any scientist will tell you to not to look at the end data, but to look at the formula used to calculate the result and the way in which the data for the study was gathered. That's what's most important.
Depending on what your formula and data is, you can get to any arbitrary result you want, which is how scientists also had studies in the 1950s saying that smoking was good for your health.