“Gee, I know I said all that about wage slavery, but who could have predicted iPhones and corn syrup. This is great!”

Read the shit you’re making claims about.

Your stance still needs to change then. Your issue isn't comparing wage slavery with chattel slavery, it's comparing slavery when the standard of living has improved.

Now this stance is still problematic, imagine we lost the civil war and the north became socialist, abolishing wage slavery. The south would have chattel slavery and the north would have no slavery. Now imagine the standard of living for chattel slaves vastly improved, and someone then tried to compare "modern day chattel slaves to wage slaves". Your stance would then be this is wildly unfair to modern day chattel slaves because wage slaves had a worse standard of living, a position we both understand is ridiculous.

Has chattel slavery been replaced with wage slavery for a large population since then? (Actually asking, not rhetorical)

If living conditions have improved for wage slaves but not for chattel slaves, then I'd imagine they would agree with you.