On the new market, they are really close. Most consumers are buying new. If we want to get pedantic, we can compare buying used systems on Facebook marketplace to cannibalize the parts and resell the others to see net cost.
I don't think most people building AM4 systems currently are buying new, or at least not everything new, simply because depending on what you're looking for there might not even be any new parts.
I don't think most people building AM4 systems currently are buying new, or at least not everything new, simply because depending on what you're looking for there might not even be any new parts.