I think you’ve got your facts garbled, or the podcast has. Up to about 20% of Neanderthal DNA has survived somewhere dispersed among humans, but some countries and backgrounds have a maximum of 3% per human.
The average is about 2% outside Africa.
"but some countries and backgrounds have a maximum of 3% per human. The average is about 2% outside Africa."
as mostly false
https://www.sciencedirect.com/science/article/abs/pii/S10406...