My point is that there is no "switch sides", because there are only 1.5 sides. Also, partisanship isn't the only force determining outcomes in the supreme court

My point is that there is no "switch sides", because there are only 1.5 sides. Also, partisanship isn't the only force determining outcomes in the supreme court, it's just the most important one for many purposes. The other major shift is actually more along the axis of social libertarian vs authoritarian, which is not as clearly divided as "republican vs democrat", especially considering the late RBG was clearly an authoritarian in some respects, despite being fairly left of center. Taking any of this as evidence that the court is non-partisan is pretty incorrect: They're consistently partisan in clearly obvious ways, even controlling for other issues.