> And it also says things like horses, chariots, steel, and other anachronistic things existed in the pre-Columbian Americas. There is no evidence (to date) to support any of those claims.
Horses definitively existed in (far enough) precolumbian America. The dominant belief seems to be that they died out (perhaps due to human hunting) at or shortly after the end of the Pleistocene, ca. 10-12kya, but there is some evidence there may have been some populations around as late as ca. 3kya, IIRC.
EDIT: of course, one must keep in mind that the horses of precolumbian America were much smaller than Old World horses, so it's not really plausible that they'd be being ridden, pulling chariots, or generally being used like Old World horses even if it is (just barely) plausible that they were around at the right time.