> And yet one of the father's of written modern English, Chaucer himself often used double negatives [0].

It's worth noting that neither of your examples has a double negative. Triple negative (the second possibly quadruple), sure, but not double.

> At this moment in time, double negatives are frowned upon.

I don't know that there's really a shift in time with the double negative, its a stylistic rule, and, much like the Pirate Code, stylistic rules in English are more what you'd call guidelines than actual rules.

Or, looked at another way, more like training wheels.