@TomTomBinks,
I agree, its just that our minds are always establishing the boundaries beyond which noone can traverse. Thats been the mantra of much paleoanthropology in the 20th century. Because the Pleistocene Ice sheets needed these "Ice free" zones to be passable (Thats almost doctrinal), weve discounted the inventiveness of our genus.
If it turns out that the argument for these artifcts are associated with some kind of Homo species , itll be at a level where these "cousins" were meat eaters and perhaps already "big brained"
and therefore capable tool makers and maybe even flotation device creators.
Neanderthals, weve been finding, were not brutes but were capable when it came to adaptation to cold and were skilled tool makers for close in driving of prey (the kind of hunting that can be done in deep snow or boreal forest.
Its also been shown thaat, much of habitation in the early North America was on the continental littoral zone. Long Line fisherman have dragged up artifacts and paleo tools from depths of 200+ feet deep.
Many archeologists (IMHO) are rather non creative when it comes to exploiting the information available about littoral zone dwelling in the mid/late pleistocene.
Were always fixated on caves nd rock overhangs. yet denisovan dwellings nd arctic H habilis made skin dwellings