It is not white nationalism to believe that countries like the United States would be better off with more babies. That belief can be held for racist reasons by racists, but it can also be held, reasonably and righteously, by people who worry about the economic consequences of demographic decline.
Bill Clinton and Barack Obama represented somewhat different party factions, but they both embodied wonkery, a vision of competence and expertise governing to some extent above ideology, in which there are assumed to be 'correct answers' to policy dilemmas that a disinterested observer could acknowledge and the right technocrat achieve.
Whatever role the structure of the Internet plays in radicalization, the root causes are still primarily sociological and political, and they will perdure and manifest themselves somewhere, somehow, no matter what YouTube suggests for your next video when you watch a Milton Friedman lecture.