In science there’s always a second opinion – some better informed than others. I can’t fault anything that John Hawks, anthropologist, has to say on his speciality, so check out his corrective to the claim humans went through a bottleneck some 70,000 years ago…
…basically some questionable assumptions have to be made to produce the proposed bottleneck at 70,000 bp. As John explains somebody hasn’t done their maths or the science media has jumped on ambiguous statements without checking a bit harder. The bottleneck can be produced by a higher mutation rate, but it would have to turn-off before the move Out-of-Africa, some 60,000 years ago, else some weird results would arise (like American Indians originating 7,000 years ago, not 14,000, or modern Asian/Australasian groups appearing 30,000 years ago, some 20,000 years too late for the Australian Aborigines.)
Assumptions about populations and isolation between them might change the picture, so only better data can bring that time period into more definite focus.