[MangoToupe]

> AFAIU the consensus opinion is that carting wheels never took hold in pre-Columbian America because of a lack of draft animals.

On hilly terrain, wheels simply aren't the best thing to use—you can't fully sustain the weight easily pulling up the hill as opposed to standing on the incline. Meanwhile we have tons of evidence of people used as couriers for relatively heavy items with a specific sort of framed backpack.

The lack of pack animals is a real thing, but domesticated horses would have seriously struggled even if they magically appeared in the pre-colonial incan empire. Even today, transportation by donkey sans-cart is often the easiest way to move a bunch of stuff around the andes without prepared roads.