A correlation between people who use a language and the previous languages they have used does not imply a correlation (or intellectual/philosophical inheritance) between the language under discussion and the previous languages used.
I've never used Haskell, so I can't speak the specifics of the observation. But I don't believe much can be inferred from the observation alone.
"A correlation between people who use a language and the previous languages they have used does not imply a correlation (or intellectual/philosophical inheritance) between the language under discussion and the previous languages used."
And yet, that is exactly the basis for Yegge's point: attributing a philosophical label based on a perceived (and incorrect) background for a group. Goose, gander. Kettle, pot.
I've never used Haskell, so I can't speak the specifics of the observation. But I don't believe much can be inferred from the observation alone.