Whatever happened in 11,000 B.C. formed the Great Lakes and annihilated the Clovis culture in North America, along with 100% of the large animals.
It was very real.
The extinctions in Europe were not so instantaneous. Took about 500 years. Mammoths, Saber-tooth Tigers etc. Gone.
Instead, we argue over mumbo- jumbo.
It's kind of like what Noah of the Bible was supposed to be enduring, though his intentions were only to do good.