In that ranking, they basically measure reputation, citations of papers in other papers and # of PhDs students. It depends how you measure quality.

Finally, I don't think being the best government in Argentine history is a very high bar to reach...

Yes, that's correct.

In a nutshell, when Argentina was rich there were very rich and very few landowners, who also controlled the goverment, and a lot of poor people that worked for them. It was feudal "capitalism". There wasn't much of a "middle class" or "rising middle class". Of course, a democracy can't work in those conditions. There were fraudulent elections, coups and, of course, the response of the mass of the poor was either following the few intelectuals of the elite that proclaimed comunism as the solution, or to cling to father figures in goverment(Perón). The people were slaves, treated as slaves, and then reacted as slaves.