As erudite and well-spoken as your argument is, I think it's simpler.

'the more learned and witty you bee, the more fit to act for Satan will you bee. ... Take off the fond doting ... upon the learning of the Jesuites, and the glorie of the Episcopacy, and the brave estates of the Prelates. I say bee not deceived by these pompes, empty shewes, and faire representations of goodly condition before the eyes of flesh and blood, bee not taken with the applause of these persons.'

- John Cotton, 1642

Stalin rounded up the intelligentsia and deported them. Mussolini stripped them of rights. Chairman Mao exported them to Tibet and Franco suggested they should be killed. Populism often rides hand-in-hand with anti-intellectualism; look at it this way: If you're in Oklahoma, and you're voting Republican, odds are you weren't in AP classes. If your political system is architecturally flawed you do better to get rid of anyone who can point it out. Of course, when your system collapses you're pretty much fucked (see: Franco, Mussolini, Stalin, etc) but you're dead by then so you don't give a fuck.

If you're of average intelligence but your opponent is of above average intelligence, you benefit by getting everyone of below-average intelligence to revile intelligence. The clever people will likely get spun up in a debate over eugenics and free will while the idiots will get their deer guns. No leader in the history of the world has ever suffered short term from steering things toward stupid.