A wolf and a coyote may be some 97% or so identical to a wolf in genetic DNA, but that doesn't mean that one cannot find genetic evidence of wolf ancestry within some coyote populations by way of crossbreeding, and be able to estimate that coyote population as having 1 to 4% wolf ancestry.
Similarly, a human and a neanderthal may be some 99% or so identical in genetic DNA, that doesn't mean that one cannot find genetic evidence of neanderthal ancestry within some human populations by way of crossbreeding, and be able to estimate that human population as having 1 to 4% neanderthal ancestry.
Neanderthals are distinctly non human.
The amount of difference you would expect to see in neutral genetic markers between human populations is AT MOST one third of what you would see when comparing a human population and the NON human neanderthal.
The evidence suggests that while the most distantly related humans shared a common ancestor within the last 100,000 years, humans and neanderthals were different populations some 250,000 years ago.
In morphology and DNA, neanderthals are distinctly not human.
They were most certainly not from a “normal” population of European humans that had rickets and were put in the Stone Age equivalent of a leper colony.
Neanderthals are distinctly non human."
Your explanation here may well be correct, but that's not what the report says. And this is not the only place I've seen those numbers.
The report says:
"the researchers found that both Europeans and Asians share 1% to 4% of their nuclear DNA with Neandertals. But Africans do not."
That is clearly bogus, and someone needs to send whoever wrote it back to remedial math class -- or maybe "scientific ethics" class.