Owen Benjamin hates jazz
If it’s not your thing, ok, but I think he’s irritated by the fact that black people can play piano better than him. It doesn’t compute. That’s where the intense antipathy comes in. He claims a philosophical objection on the basis of dissonance, you’re only supposed to use notes in the scale, othewise there’s tension, dissonance. Bach had it right, Pachabel’s Canon in D, let’s keep it pure. But even in a standard major key, the seven chord is diminished, a tension chord. Dissonant, but it resolves to the root. Normally dissonance is transitory, tension-and-release. In a minor key, the two chord is a tension chord. So in standard Western harmony, dissonance has its place, but you don’t overuse it.
I love classical, but classical abandoned the rules before jazz came on the scene. The premiere of Igor Stravinsky's ballet The Rite of Spring on May 29, 1913, at Paris's Théâtre des Champs-Élysées, is famously known for sparking a massive riot. Owen genuinely is racist, his name is one of the twelve tribes of Israel. So it really does bother him that he’s no Art Tatum.