I think it's self-evident that partisanship in the descriptive sense of hte word not the categorizing into Ds and Rs sense of hte word has gotten more rancorous and intense fairly recently (at least by the political standards of the last half century or wahtever, people were way more crass back in the day).
SCOTUS picks are more partisan in the sense that presidents rely more on written opinions and other stronger indicia of political leanings.
The Heritage Foundation, Federalist Society and Co. have done their work well and upheld their refrain of "No More Souters."