The issue is that there is clear genetic evidence that the current indigenous population of the Americas arrived onto the continents around 14KYA-15KYA, and all their various land claims and special rights / privileges fundamentally derive from the argument that "They were here first."
Whoever the people leaving footprints at White Sands were, the genetic evidence is clear that they weren't the ancestors of North America's current indigenous population. They were a genetically distinct people group (My suspicion is they would have been more closely related to Australian Aborigines) and are in fact the ones "Who were here first." Accepting that there were already people in the Americas when the current indigenous population arrived, would undermine the land claims of the current North American indigenous populations, and would force them to reckon with the fact they too are colonizers / settlers who displaced an earlier population, likely through violence and possibly even outright genocide, as apart from some isolated groups in the Amazon, there's no genetic evidence the current indigenous population of the Americas meaningfully intermixed with any other populations once they arrived onto the continent as we would expect were the existing population absorbed into the new population through interbreeding.
This is in large part why so many indigenous groups are adamantly opposed to participating in genetics studies, or allowing archaeologists to conduct digs in their "Traditional territories" as a great many indigenous groups actually have "Oral traditions" that there were already people in the Americas when their ancestors arrived, and they know that further study will contradict the narrative that "They were here first," and could eventually invalidate their "Blood and soil" based land claims.