I need more people to understand that the spaniards were genuinely shocked by the size and beauty of native american cities. It is not uncommon for one of them to recount that they were more beautiful and impressive in scale than anything they had ever seen in Spain.

Also like, even if they were, so what? Someone or a culture being 'less' developed is not a good excuse for colonising, genociding etc it. Offer help with no strings attached, sure. But anything more than that is wrong and unethical to the highest degree.

The Americas were mostly in the copper age though. They however unlike in Africa, Asia and Europe seem to not have used it as much for producing practical items, but more for art.

Also the late stone age did have fairly complex societies as well. Not just in the Americas.

I have never really heard excuses for it. Its just something that happened. Its similar to europe with the original peoples of places displace, diluted, or destroyed.