I could make the (true) argument that while this almost (their descendants are still around) happened, all of humanity was not extinguished.

But it's an interesting point. While the world never ends, entire peoples and nations do get extinguished with some regularity, and having people around who always look for ways this can happen could serve a credible evolutionary purpose, even though they're almost always wrong.

Their civilization did collapse though. There are different people living on all that land but I don’t think anyone seriously is worried about people or cockroaches going extinct