His partisanship was always circumstantial. I think he's renewing his position based on the increasing polarisation rather than actually "switching teams". It'

His partisanship was always circumstantial. I think he's renewing his position based on the increasing polarisation rather than actually "switching teams". It's more like political divestment, as the costs of polarisation have increased. His actual values - basic libertarianism like open borders and free trade and limited government - haven't changed at all. That's precisely why he never backed Trump, and instead continued plugging the values he espoused even as that drew fire from Republicans. For instance: note that he donated a lot more to Rep candidates than to Dem candidates, but it was almost exclusively where the relevant contest involved a pro-markets versus anti-markets debate. As Republicans have moved away from markets into populism, his spending is less and less partisan.