I appreciate the clarity the article uses in the factual support for the ultimate theory, building on each inferential step that seems pretty obviously correct. The stuff that's actually presented as being fairly certain:

The fossil record shows many lines of archaic homo sapiens whose physical features don't share modern homo sapiens' "juvenile" baby face characteristics.
The dating of those fossils and the migration patterns of our known ancestors suggests that these archaic homo sapiens aren't actually our ancestors, but were outcompeted by our branch.
The anthropological record shows that these archaic homo sapiens weren't as dominant as our ancestor branch, but were close and could hold their own. Apparently the ancestors of modern humans never lost territory, even if it took millennia to displace other hominids.
These archaic branches had some limited tool use, and some evidence of trade and ceremonial burial.

The article presents theories about our branch being less violent, having less aggression, able to build lasting alliances with larger groups of tribes. But it's grounded in some interesting facts that are interesting, in themselves.