A decade ago, archaeologists would have been completely flabbergasted to find evidence that people were living in North America 18,000 years ago. At that point, the oldest evidence of people anywhere on the continent dated to around 13,000 years ago, in the form of long projectile points with flutes: narrow notches at their bases, creating a shallow groove to fit a wooden shaft for hafting.
This is not true. A decade ago, it is true that the "clovis clique" was in full bloom, stomping all over the research and sometimes whole careers of anybody who cast doubt on the "clovis first" narrative.