DNA from extinct hominin may have helped ancient peoples survive in the Americas

Published in the jounnal science https://www.science.org/doi/10.1126/science.adl0882

well could it be argued that they are not extinct, since they interbred and live on in many populations? just like Neanderthals might be said to live on in European populations?

Is it a matter of semantics?

Will white skinned "Causasian" populations be extinct in 20,000 years when they've alö interbred? Outside the occasional albino?