I’m not totally convinced. Certain statistics you cite were preliminary — once all votes were counted, Trump turned up with roughly 62.9M votes, more than both McCain’s and Romney’s totals (though less than Clinton’s 65.9M votes). Furthermore, it’s not clear how the apathy of the hundred million or so politically-disengaged eligible voters can be blamed for Trump’s victory, since this phenomenon has existed for many decades, and has resulted in both people like Trump, a pandering nihilist demagogue with neither the experience nor the maturity necessary to run a powerful 3M-person bureaucracy, as well as Obama, the nationally-renowned scholar of constitutional law with a talent for uniting disparate political forces and developing a coherent long-term vision, especially in 2012, when his opponent ended up being saddled with similar political baggage as Clinton (though of course, the 2012 and 2016 elections were far from identical).
What was really remarkable about Trump (at least from my perspective) was not that he seemed to cause or benefit from voter apathy, but that his approach of pandering to the most extreme elements of the right likely succeeded *increasing* turnout among certain groups, without costing him too many votes on the center. I suspect that a highly tech-savy propaganda campaign with no compunctions about lying or distorting the truth plays a large role, as did the increasing reliance of a large part of the population on social media to gauge popular opinion and “crowd-source” their news, which radically increases the vulnerability of the American political system to the tools of information warfare.