Why are such hypothetical questions always directed toward Republican (I won't say conservative) candidates? Why wasn't Obama ever questioned in this way? "Which industries would Obama have to nationalize before you'd call him a communist?" "How many people would have to die from rationed healthcare before you'd call for the end of Obamacare?"
Because such rhetorical questions are weaponized by Leftists. They’re not in search of enlightenment, they’re a form of accusation; that the question is asked _at_all_ deliberately demeans (at least in the Left’s eyes) the person being questioned.
And because real journalists, who would actually ask such questions you suggest, were never allowed anywhere close enough to actually ask Obama et al such relevant questions.