Leszek, I don’t think your reply invalidates what blargey said. Showing that "down" can also be neutral, impactful or enthusiastic (like "down for" or "get to the bottom of") is useful, but it adds nuance rather than disproving the broader pattern that up = good / down = bad runs deep across languages.

It certainly disproves that it's a pattern without exceptions, and therefore invalidates or at least questions the idea that every instance of up and down (like which way up north is) has to be mapped to good and bad.

It's all just anecdotes vs. anecdotes. The alleged "broader pattern" is not proven by one any more than it is disproven by the other. (For what it's worth, I do think there is a cultural pattern, especially in biblical metaphors, but in general use it's far weaker than what TFA is making it out to be.)