It has one of the best discussions of contrast I have seen; very timely given the trends for low contrast design that seem prevalent combined with my now over 40 eyes (darn those kids!)
I'm a decade younger than you and I still bristle every time I see someone disparage black-on-white. #000 on #FFF looks fine, guys, and it looks way, way better than the #BBB on #CCC that you're about to publish. You're overthinking it.
Black and white, but take the edge of a little.
It's honestly pretty cool to see this. I'm glad that the US government (or at least this one particular agency) takes accessibility so seriously.
In every real world scenario there will be a multitude of colors present that impact accessibility. It is almost never so simple as a single text color on a single background color.