Now that new ice core evidence shows CO2 comes AFTER global warming, why is this AGW theory still around?

Sure, in the beginning it looked like there was a tight correlation between CO2 and global temperatures. The theory of CO2 being a driver of climate change was born. But more recent data (more accurate measurements) have proven that the increased/decreased CO2 levels follow warming/cooling by about 800 years. And they now know why this is ("outging" of CO2 from warmer/cooler oceans.) I don't know whether man causes climate change, but it's been proven now that CO2 doesn't cause it. Why are we still talking about CO2? Did someone not get the memo?