We know that the people behind the Clovis material culture weren't the first people in the Americas. It took decades of work by academics like Tom Dillehay, but that's been the status quo since the 90s.

We don't know what happened to the preclovis groups. It's likely they were absorbed/became ancestral to later groups like those behind Clovis culture rather than erased, but the evidence is too scarce to say anything definitive.