You might argue that makes them good at playing the political system but not at anything intellectual.Truss - opportunistic, sure, but you don't get to PM by being unable to enlist the support of your party even if she managed to alienate most of them within a few weeks.
GWB - some say he was basically the figurehead of a neo-conservative movement within the Republican Party but he was also Governor of Texas and by all accounts smarter than what is commonly portrayed in the media.