Don’t forget the fact that the mechanism used a model made by Hipparchus, but after Hellenism the Greeks adopted the Ptolemaic geocentric view of the cosmos with epicycles and stuff.

Epicycles delivered more precision but at the cost of much greater complexity. Ultimately it took Kepler to simplify it even more through his iterative equation though I can’t imagine how to turn that into a mechanical model.

The Antikythera mechanism was possible because of the simplicity of the underlying solar system model that lent itself to easy implementation by gears. It’s much more elegant than even modern methods of computing orbits. That’s the main surprise I find in its design…how much they could simplify it (and not how complex the mechanical construction is).