Worldbuilding

Yes and they also got rooted out by the inquisition

No they didn't. The radical reformation took place in the sweetspot between the end of the so called "Papal inquisition" and the beginning of the so called "Roman inquisition", and the Spanish inquisition had little power to enforce catholic doctrine in the lands where it took place.
And by the time the Roman inquisition kicked off, Anabaptists had taken over entire towns and Protestantism taking over entire countries. The inquisition can't do shit to you if you're in a non catholic town..

Now they did kill a bunch of anabaptists, don't get me wrong. But it was aristocrats, catholic and protestant alike that ended the radical reformation as a political (But not theological) movement.
Müntzer as a representive of what we might call the politial wing (Although they would make no distinction) of the radical reformation was killed by a protestant (Phillip of Hesse) at the behest of a Catholic bishop.

Incidentally Phillip of Hesse was also a patron of Anabaptists in his own lands. But only the ones, like Zwingli, who championed the aristocracy.

The concept of an enlightened monarch is a modern fairy tale invented by countries with constitutional monarchies

No. It was explicitly a counter to the idea of a constitutional monarchy. It grew out of enlightened absolutism as a political philosophy. Its champions include Frederick the Great, Catherine of Russia, and Denis Diderot (Of the slight misquote, although true in sentiment, "Men shall never be free until the last king is strangled with the entails of the last priest")

I leave it as an exercise to the reader to figure out if the man who wrote "Et ses mains ourdiraient les entrailles du prêtre, Au défaut d’un cordon pour étrangler les rois" and two famous autocrats are fans of constitutional monarchism.