I'm not an expert at all, but your response made me curious as to why that (presumably humorous) aside would have been thrown in.
Anyway, my research, such as it is, took me as far as the Wikipedia article on Ecclesiastes[0], which maybe provides soft support for the claim?
The presence of Ecclesiastes in the Bible is something of a puzzle, as the common themes of the Hebrew canon—a God who reveals and redeems, who elects and cares for a chosen people—are absent from it, which suggests that Kohelet had lost his faith in his old age.
Anyway, I hope that this won't discourage people from reading the entire thing, which I thought was well written and well worth the time.