Did the columbian exchange bring more changes to the americas or to europe

It is hard to quantify, but I would say: yes, especially as far as human populations are concerned. Columbian exchange involved viruses and bacteria that caused sicknesses, and those were harder on the American population: many Americans died from European diseases.

Some Europeans died too, for example from syphilis, but not as many.

It allowed for things to be produced much more quickly and efficiently