Concur with you on this, Ken, though I will add another thought on "causation".
There are some who believe the Younger Dryas came about after the antecedents of today's Great Lakes found an outlet and dumped huge quantities of fresh water down the St. Lawrence and into the Atlantic, via the Ottawa River and a stretch called the "French River". Today, the French River flows westward into Lake Huron between Parry Sound and Sudbury, Ontario. The supposition is that during the dump of glacial melt, it flowed in the opposite direction to somewhere near Ottawa and into the Ottawa River.
I wasn't there, so I can't say definitively.
But I do note that mammoths and other megafauna survived quite well in Eurasia, right alongside humans hunting them, until about the same time they disappeared from America. (Even until the time of the Greeks and early Rome, on Wrangell Island.)
