What you’re missing here is in today’s society, education is highly correlated with wealth.
While education does not necessarily mean a person came from a middle to upper class family, huge numbers of middle to upperclass families send their children to school.
So what your statistic is actually showing is that those who cannot afford to go to school, or those that chose to work instead are voting for Trump.
You are saying what everyone else always has been- Trump has won the working class vote. Yes, he has lost the liberal college student’s vote, but he sure kills it with nearly everyone in a labor job.