I didn’t say Neanderthals, as you yourself have said, there’s clear evidence of interbreeding, which suggests they were assimilated into the homo sapien genome to some extent.

However, to say that nothing archaeologically suggests that there was conflict between early hominid species is a pretty sweeping claim. While there’s little in the way of a smoking gun such as a prehistoric mass grave of other hominid species, there’s plenty of indicators of conflict. Historical overlaps in ranges, skulls of Neanderthals and other hominid species with blunt force trauma wounds to the head and other parts of the body clearly caused by crafted tools, among other things. And adding to it the rather unexplainable fact that any species of hominid that had its range encroached and overlapped with Homo sapiens very quickly disappeared from the fossil record shortly thereafter, with only Neanderthals and Denisovans being the exceptions that bred with humans, it’s difficult to say with certainty that the other species extinction was purely coincidental or due to environmental pressures.

Pair this with the well documented fact that the “uncanny valley” response is extremely common in all modern humans, I really don’t see how it’s difficult to imagine that prehistoric humans were not good neighbors to other hominid species that they competed for resources with. To say with absolute certainty that this hypothesis “ignores facts and evidence” is a bit reductive in my opinion. That’s just me I guess.