Comment by kragen
Switzerland has been preventing authoritarianism since before it was cool. Like, for 700 years. (With a brief interruption when they were invaded and overthrown by Napoleon.) So their system for the first 600 of those 700 years was the best system for preventing authoritarianism; a lot of it survives today.
This would be a wrong argument even if your premise about Switzetland was factually true (it's not).
It's like praising Danish architecture for its earthquake-resistance since no Danish building ever collapsed in an earthquake. It fails to account for the fact that Denmark never gets any significant earthquakes.
You can't tell how good a system is at resisting descent into authoritarian rule unless wannabe-autocrats have tried several times, amassed some support to achieve their goals, and the democratic institutions held against them. This never happened in Switzerland, not even in the 1930s: the ability of the Swiss constitution to precent authoritarian backsliding is untested.
(But as a side note, what you're saying is not factually correct. The Swiss constitution is from 1848, and before Napoleon only Schwyz, Uri and Unterwalden would be considered nonauthorian. Many cantons, like Bern, were ruled by birthright autocratic families, and had no popular vote whatsoever.)