Maya hieroglyphs must have been readable across several spoken languages, the way Chinese characters or Latin were.

Archaeologist and director of the Maya Exploration Center

There must have been a way that multiple languages understood the same writing system. Or maybe there was something like Latin. You know how there was a period in Europe where most people were illiterate and there was this priesthood who all understood Latin and they wrote in Latin? Maybe the hieroglyphs represent a kind of Latin in the ancient Maya world.