My claim wasn't that it's unfamiliar - which it is - but that's it's terrible. What's striking is the data, not the visualization applied to that data. I think the effect would be just as dramatic with an x-y scatter plot, and it would have the benefit of being easier to read.

This graph also eliminates seeing if there is a correlation between money spent per individual and life expectancy. On a scatter plot, if there was a correlation, we would expect to see the data fall in some line. If a data point was outside of that line, then it would be obvious.