There is a misconception that “divine right” of kings was a long standing tradition. It’s a product of state centralization in 16-17th century Europe.

The hereditary rule of kings had to be justified somehow so a legal fiction of divine right was established. As to how many people actually believed in it we can’t really know, however there was pushback almost immediately, for example Republicans in English Civil War, Dutch Republic, various Italian and German states… Meaning to say It wasn’t a universal concept even during the peak of its popularity.

Earlier Medieval states often operated as elective monarchies, especially those of Germanic origins. Holy Roman Empire held on to the elective monarchy from 962 to 1804. In contrast France, despite common origins, slowly moved to the “divine right” concept, and pretty much pioneered early modern absolute monarchy.

There is much more to be said for states in the rest of the world. Although monarchies, Japan and China had completely different justifications as to why the king is a legitimate king (and fall very much in the divine right category). Then were are various Native American nations with government systems which seem unusual from today’s perspective.

All this is to say that while some type of monarchy was the most common system before the Industrial Revolution, it wasn’t universally accepted. And even when it was it wasn’t necessarily of the divine right kind.