North American natives were effectively isolated from the rest of the world until the 15th century.

Europe, Africa, the Middle East, China, India, and southeast Asia had basically all been interconnected for millenia.

You had the Roman empire, the hellenestic kingdoms, Mongolian empire, trade routes of the Indian Ocean, trade routes like the Silk Road, etc... that had people, goods, and ideas transferring from one group to another for centuries.

That means technology, religion, science, and more from China can make it to Europe and have influence.

The Americas had some civilizations that were pretty damn advanced. The Inca somehow made a huge empire in the mountains with only humans and llamas. The Aztec basically had a capital that rivaled any city in europe at the time of its destruction.

If given time, these groups may have become more powerful, but the odds were against then when it came to trade and new ideas. There just weren't as many people involved there as in the Eurasian trade networks