Atlantis is usually put at "just before history" -- Atlantis was destroyed and then their survivors did all the impressive stuff around the world like building

Atlantis is usually put at "just before history" -- Atlantis was destroyed and then their survivors did all the impressive stuff around the world like building the pyramids and Stonehenge, so around ~5000 years ago. You're looking at something more like 50,000 years ago, so something like the Toba population bottleneck (which probably didn't happen 70,000 years ago). The cleansing of saidin in the previous turning of the Wheel, might work.