I think the point being made is that remembering is a huge if not key aspect of learning anything, and people underestimate the importance of memorization. Maybe that title is a bit misleading, could've been "No serious learning can happen without memorization" but that doesn't flow as well.
If anything the problem used to be that we overestimated the importance of memorization. Maybe it's changed now, but trying to free cognitive load is important. It's the same reason why literary societies beat oral ones. The emphasis on memorization was reduced.
