> Commoners did not have this custom until the twentieth century
It really depends on the culture. Having the groom give the bride something of value is a quite old tradition for Jewish weddings, including "commoners" (read: all Jews, pretty much). A ring was in fact a quite common such gift going back a long way.
That said, if a ring is used in this case it must traditionally be a plain band with no stones; we're not talking diamond rings here.
This site isn't trying to upend the artificial customs that we've come to cherish, just to substitute one costly part of it with a cheaper indistinguishable alternative for all the reasons he described
But you're still buying into the concept of the gifting of rings, when this is a recent phenomenon created by De Beer's. Unless they were European royalty, your great-great-grandparents did not exchange rings. Commoners did not have this custom until the twentieth century. When you suggest getting non-diamond rings, you perpetuate the expectation that people should exchange rings, continuing De Beer's advertising campaign.
My wife and I got married without exchanging any rings for this reason. I thought that I might need to explain my position on rings to friends and family, but we've never gotten so much as a comment about it.
(BTW, your link to the Atlantic article 404s.)