The Perils of Presidentialism

Linz argues that Presidential democracies are less stable than parliamentary ones in countries with polarized political views because competing executive-legislative democratic legitimacy and the timed nature of Presidential terms exacerbate extremism and elevate what would be government crises into regime ones.

Linz uses the US as an example of a moderate population where a Presidential democracy works. Does increasing polarization challenge this? Trump's abuses of power fall neatly in line with Linz's examples of how Presidentialism tends to exacerbate polarization and lead to regime crises. Has America been more polarized in the past, ex. with Andrew Jackson? Was Trump a temporary surge in instability or the indicator of a larger trend?