Naval Enthuiast

The Grand Pensionary of Holland decided to personally get involved in naval strategy during the Second Anglo-Dutch War. This meant boarding a ship(while seasick) and pressuring everyone into following his plans—so much that the crew was genuinely scared of him while laughing behind his back[4]. To his credit, it worked. The Dutch won a stunning victory at the Raid on the Medway under Admiral De Ruyter.

Got stabbed, can I take a day off?

On his ten-minute walk home from work, Johan was attacked by assassins and almost died. His reaction? Writing a letter asking for sick leave. He then proceeded to report the events and the coordinates of his wounds, like a crime scene investigator.[2]

Annuity calculations, anyone?

Who pitches cutting-edge probability theory to the States General in 1671[3], one year before total disaster? Johan. Forget the military and threat of French invasion. Johan thought annuities were the perfect financial tool for the government, and he really liked math. 

Provincial Atoms

In his pursuit of "True Freedom", Johan took decentralization to an unfortunate extreme, spending two decades meticulously reinforcing an oligarchic system(the Civilization VI equivalent of enabling “Infinite Congress” mode). The House of Orange "represented unity and growth"[5], "True Freedom" represented Holland-centric elitists and regional ego-tripping. Guess which was more popular in 1672.

Why is everyone so offended?

In 1656, Johan tried to simply partition philosophy and theology like they were files on a computer[4]. His "compromise" was basically to say, “Let’s be nice to each other and pretend our beliefs don't matter.” Spoiler: the preachers were not amused.