The Koch network is VERY anti-Trump, and a significant percentage of the plutocrat class follows their lead.

Because sure, they care about tax rates and regulations, but they care even more that the world remain stable. Because the one thing that can erase wealth inequality is big wars that destroy the wealth of the wealthiest. They need the US to maintain its control of the shipping lanes, to maintain its alliances, to maintain the dollar’s status as the world’s currency.