One piece of evidence for the second is to notice how nations with small populations tend to cluster near the top of lists of countries by per-capita-GDP.

1) So do nations with very high taxes, i.e. Nordic countries (or most of Western Europe for that matter).

One of the outliers (Ireland) has probably been knocked down a few places recently, as a result of a worldwide crisis that might well be the result of excessive deregulation.

2) In very small countries, one single insanely rich individual will make a lot of difference to average wealth, even if the rest of the population is very poor. I think Brunei illustrates the point. So I'm not sure the supposedly high rank of small countries is indicative of anything (median GDP would be more useful).

3) There are many small-population countries at the bottom of the chart too.

Upvoted.